• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 34
  • 5
  • 4
  • 1
  • 1
  • 1
  • Tagged with
  • 51
  • 51
  • 24
  • 20
  • 8
  • 8
  • 7
  • 6
  • 6
  • 5
  • 5
  • 5
  • 5
  • 5
  • 4
  • 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.
31

Natural Gradient Tracer Tests to Investigate the Fate and Migration of Oil Sands Process-Affected Water in the Wood Creek Sand Channel

Tompkins, Trevor 08 September 2009 (has links)
The In Situ Aquifer Test Facility (ISATF) has been established on Suncor Energy Inc’s (Suncor) oil sands mining lease north of Fort McMurray, Alberta to investigate the fate and transport of oil sands process-affected (PA) water in the Wood Creek Sand Channel (WCSC) aquifer. In 2008, the ISATF was used for preliminary injection experiments in which 3,000 and 4,000 L plumes of PA water were created in the WCSC. Following injection, the evolution of the plumes was monitored to determine if naphthenic acids (NAs) naturally attenuated in the WCSC and if trace metals were mobilized from the aquifer solids due to changes in redox conditions. Post-injection monitoring found groundwater velocities through the aquifer were slow (~3-10 cm/day) despite hydraulic conductivities on the order of 10-3 m/s. While microbes in the WCSC were capable of metabolizing acetate under the manganogenic/ferrogenic redox conditions, field evidence suggests naphthenic acids behaved conservatively. Following the injections, there was an apparent enrichment in the dissolved concentrations of iron, manganese, barium, cobalt, strontium and zinc not attributable to elevated levels in the PA injectate. Given the manganogenic/ferrogenic conditions in the aquifer, Mn(II) and Fe(II) were likely released through reductive dissolution of manganese and iron oxide and oxyhydroxide mineral coatings on the aquifer solids. Because naphthenic acids make up the bulk of dissolved organic carbon (DOC) in the injectate and are apparently recalcitrant to oxidation in the WCSC, some question remains as to what functioned as the electron donor in this process.
32

Chemical oxidation of refinery spent caustic liquor containing naphthenic acids

LI , Sin-Jia 21 June 2012 (has links)
Spent caustic liquors (SCL) generated from crude oil refineries have characteristics of high COD (chemical oxygen demand) contents and relatively small generation rates as compared with general wastewater ones. The odorous naphthenates, phenolates, and sulfides in the liquors adversely affect the normal operation of the related wastewater treatment plants and effluent water qualities. This study aims at the reduction of COD in a naphthenic spent caustic liquor generated from a domestic refinery with crude processing and naphtha cracking units. Primary tests indicated that around 50% of the COD in the SCL could be biodegraded. Chemical oxidation methods were tried to possibly upgrade the COD removal. Experiments indicated that acidification of the SCL sample to pH 2-3 could reduce the COD from an average of 51,600 to 20,800 mg/L by removing the separated naphthenic acids. Fenton¡¦s method with oxidants of 20 mL/L 35% H2O2 and FeSO4.7H2O 5 g/L, oxidation time of 1 hour at conditions of pH 2-3 and 80-100oC, could reduce the COD of the acidified SCL from an average of 20,800 to 11,100 mg/L. The overall COD removal was around 78% and the efficiency is comparable to that of a traditional Wet Air Oxidation (WAO) process of around 75%. Economic analysis indicated that for treating the SCL of 80 m3/day by the traditional WAO process, an initial equipment cost of 10 millions USD and annual operating cost of around 1.5 millions USD are required. By the developed acidification-Fenton¡¦s process, an initial equipment cost of 0.7 million USD and annual operating cost of around 0.5 million USD are expected. The developed process can be superior to the WAO one.
33

The Effects of Oil Sands Process-Affected Waters and their Associated Constituents on Fathead Minnow (Pimephales promelas) Reproductive Physiology

Kavanagh, Richard James 10 January 2013 (has links)
As part of their reclamation plan, oil sands operators propose to transfer the mature fine tailings, which are a by-product of the oil sands extraction process, to open-pits and cap them with either a layer of surface water or oil sands process-affected waters (OSPW). These oil sands pit lakes are expected to develop habitats with productive capabilities comparable to natural lakes in the region. The studies presented in this thesis evaluate the potential impact of OSPW and its associated constituents [i.e. acid-extractable organics (e.g. naphthenic acids; NAs) and salts] on the reproductive physiology of adult fathead minnow (Pimephales promelas). Through 14-21 day fathead minnow reproduction assays it was demonstrated that aged OSPW can impair spawning, lower plasma sex steroid concentrations, and reduce male secondary sexual characteristics. The acid-extractable organics in OSPW were demonstrated to have an adverse effect on fathead minnow reproductive physiology. Other studies showed that the high salinity which characterizes OSPW also influences toxicity. When fathead minnows were exposed to the OSPW extract and 700 mg/l of NaHCO3, the NaHCO3 reduced the inhibitory effects of the extract on the numbers of reproductive tubercles and plasma testosterone levels by reducing the uptake of NAE to the fish. Embyro and larval bioassays also revealed that NaHCO3 reduces the acute toxic effects of the OSPW extract. An assessment of a wild population of fathead minnows inhabiting an OSPW pond determined that there were differences in the condition factor (CF), gonadosomatic indices (GSIs), liver somatic indices (LSIs), male secondary sexual characteristics, and 11-ketotestosterone concentrations in the fathead minnows from the OSPW pond relative to fish collected at reference sites. The opercula of fathead minnows from the OSPW pond also differed from those of reference fish and an examination of the gills revealed that were a number of proliferative and degenerative alterations relative to reference fish. Collectively, these studies demonstrate that aged OSPW has the potential to negatively affect the reproductive physiology of fathead minnows and suggest that aquatic habitats with high NAs concentrations (>10 mg/l) will have adverse effects on fish. / Canadian Natural Resources Ltd., Canadian Water Network, Canadian Oil Sands Network for Research and Development (CONRAD), Imperial Oil Ltd., NSERC, Shell Canada Energy, Suncor Energy Inc., Syncrude Canada Ltd., and Total E&P Canada
34

Characterization of the dissolved organic matter in steam assisted gravity drainage boiler blow-down water

Guha Thakurta, Subhayan Unknown Date
No description available.
35

Estudo de adsorção de ácidos naftênicos a partir de correntes de hidrocarbonetos / Study of adsorption of naphthenic acids from hydrocarbon stream

Juliana Pereira Silva 04 May 2007 (has links)
Ácidos naftênicos correspondem à complexa mistura de ácidos carboxílicos presentes no petróleo, responsáveis diretamente pela sua acidez e pela sua corrosividade em fase líquida durante o refino. Tais compostos também estão presentes nas frações destiladas do petróleo, causando diversos problemas na qualidade final do produto. Uma possível forma de remover esses ácidos das frações destiladas é através da adsorção em materiais porosos. Contudo, os resultados até então apresentados indicam que resinas trocadoras de íons seriam os melhores adsorventes destes compostos, o que poderia aumentar o custo do processo e diminuir sua viabilidade. Neste trabalho, dois adsorventes comerciais (argila e alumina ativada) foram caracterizados por diversas técnicas físico-químicas e avaliados quanto à sua capacidade de remover os ácidos naftênicos de frações médias e pesadas de petróleo. Avaliou-se, ainda, para fins de comparação, o comportamento de ácidos naftênicos comerciais em óleos sintéticos preparados com óleo mineral. Em complementação, a corrosividade do aço carbono nos meios estudados foi também verificada. A argila apresentou maior afinidade com os ácidos naftênicos, tendo capacidade de adsorção superior e cinética de processo ligeiramente mais rápida às da alumina para as cargas sintéticas. No entanto, em virtude da maior concorrência pelos sítios de adsorção, apresentada pelos outros componentes presentes em óleos reais, observou-se uma perda na eficiência para estas amostras. Neste caso, a alumina apresentou melhores resultados. Embora ambos adsorventes tenham apresentado boa capacidade de remoção do soluto, a resina trocadora de íons ainda apresentou resultado mais eficaz para as amostras reais. Nas condições desse estudo, a taxa de corrosão do aço nas amostras sintéticas e em duas das reais não foi significativa e apenas uma delas apresentou-se corrosiva (Óleo 1). No entanto, a remoção dos ácidos naftênicos por adsorção conseguiu reduzir a taxa de corrosão neste meio em até 99% / Naphthenic acids comprise a complex mixture of carboxylic acids that are present in petroleum. They are directly responsible for the oil acidity and its corrosiveness in liquid phase during the refining process. Such compounds are also presents in the derivatives, causing several problems to product quality. A possible way of removing these acids from those oil fractions is using the adsorption process in porous solids. Nevertheless, results presented so far show that ion exchange resins would be the best adsorbent for these acids, which could make this process very expensive. In this work, two commercial adsorbents (clay and activated alumina) were characterized by several physical-chemistry techniques and evaluated concerning their capacity of removing naphthenic acids from average and heavy fractions of crude oil. For comparison the behavior of commercial naphthenic acids in synthetic commercial samples prepared with mineral oil was also evaluated. In addition, the carbon steel corrosiveness in the studied systems was verified. Clay adsorbent presented better affinity with the acids, showing a greater capacity and a faster kinetics than alumina for synthetic oils. However, because of the higher competition with the other components present in real oils for the adsorption sites, a loss of efficiency for these samples was observed. In that case, alumina showed better results. Although both adsorbents have showed good capacity of removal of acids, the ion exchange resin still presented the best results for real samples. At the conditions of this study, the steel corrosiveness in the synthetic oils, as well as the data obtained for two of the real ones, was not significant, and only one of the real samples (Oil 1) corroded the carbon steel coupon. However, the naphthenic acid removal was able to reduce the corrosiveness in this medium up to 99%
36

Avaliação do processo adsortivo para remoção de ácidos naftênicos presentes em mistura modelo de querosene de aviação utilizando adsorvente do tipo MCM-14 modificado

NASCIMENTO, Graziele Elisandra do 15 January 2016 (has links)
Submitted by Irene Nascimento (irene.kessia@ufpe.br) on 2016-06-20T18:14:17Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TESE COMPLETA FINAL - GRAZIELE NASCIMENTO.pdf: 1640569 bytes, checksum: b37271f18a2ccb0018a4524168b48c7a (MD5) / Made available in DSpace on 2016-06-20T18:14:17Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TESE COMPLETA FINAL - GRAZIELE NASCIMENTO.pdf: 1640569 bytes, checksum: b37271f18a2ccb0018a4524168b48c7a (MD5) Previous issue date: 2016-01-15 / PRH-28 ANP / A presença de ácidos naftênicos no querosene de aviação (QAV) implica em um aumento de sua acidez com efeito corrosivo elevado, diminuição da estabilidade térmica, formação de sais insolúveis e depósitos de carbono. A remoção desses compostos por adsorção é considerada uma alternativa eficiente, uma vez que podem ser recuperados, purificados e comercializados para outros fins. A síntese e caracterização de peneiras moleculares mesoporosas do tipo MCM-41 com potencial aplicação em adsorção e catálise vêm sendo bastante estudada em função de suas características, como elevada área superficial, diâmetro e volume de poros. Neste contexto, este trabalho propôs a síntese de adsorventes do tipo MCM-41 modificados, visando à remoção de ácidos naftênicos em mistura modelo de QAV (ácido n-dodecanóico em n-dodecano). Os adsorventes MCM-41, Sr-MCM-41, La- MCM-41, Ce-MCM-41, Sr-La-MCM-41, Sr-Ce-MCM-41 foram sintetizados pelo método hidrotérmico e caracterizados pelas técnicas de análise termogravimétrica (TG), difração de raios-X (DRX), adsorção/dessorção de N2 através dos métodos Brunauer, Emmett e Teller (BET) e Barrett, Joyner e Halenda (BJH), espectroscopia na região do infravermelho por transformada de Fourier (FT-IR), microscopia eletrônica de varredura com espectroscopia de energia dispersiva por raios-X (MEV/EDS) e pH do ponto de carga zero (pHpzc). Foi realizado um estudo para seleção do adsorvente a ser utilizado nos estudos de adsorção. Com o adsorvente selecionado, foram realizados estudos cinéticos e equilíbrio de adsorção em sistema de banho finito. A partir dos dados obtidos, foi avaliado o sistema continuo de leito fixo e os ciclos de adsorção/dessorção. O método hidrotérmico foi eficiente, conforme os resultados obtidos pelas análises de caracterização, uma vez que após a incorporação dos metais, os materiais mantiveram a estrutura padrão da MCM-41. A partir do estudo do pHpzc verificou-se que a incorporação do metal alcalino terroso Sr aumentou a basicidade de todos os materiais. O adsorvente Sr-Ce-MCM-41 apresentou maior estabilidade térmica, bem como maiores volume e diâmetro de poros, apresentando também uma maior capacidade adsortiva. O estudo cinético permitiu verificar que o equilíbrio foi atingido após 420 minutos, com capacidade de 0,64 gác.g-1 ads e % de remoção de 82,5%. A isoterma de adsorção apresentou comportamento do tipo IV e a maior capacidade adsortiva quantificada na faixa de concentração estudada foi de 0,8 gác.g-1 ads. O modelo cinético de Langmuir- Freundlich e o modelo de Brunauer, Emmett e Teller (BET) representaram de forma satisfatória os dados experimentais da cinética e equilíbrio de adsorção em sistema de banho finito. No sistema de leito fixo, os tempos de ruptura e saturação da curva foram afetados pela variação da vazão e da concentração de alimentação do leito. Os dados experimentais foram ajustados ao modelo de Langmuir-Freundlich, uma vez que foram desprezados os efeitos de resistência à transferência de massa e de difusão. Os estudos de adsorção/dessorção indicaram a possibilidade de recuperação de ácidos naftênicos visando seu posterior aproveitamento e aplicação. O adsorvente estudado Sr-Ce-MCM-41 apresentou potencial para a remoção de ácidos naftênicos presentes em QAV modelo nas condições estudadas. / The presence of naphthenic acids in the aviation kerosene (jet fuel) implies an increase in its acidity with high corrosive effect, decreased thermal stability, formation of insoluble salts and carbon deposits. The removal of these compounds by adsorption is considered to be an effective alternative, since they can be recovered, purified and sold for other purposes. The synthesis and characterization of mesoporous molecular sieves MCM-41 type with potential application in adsorption and catalysis have been extensively studied due to their characteristics, such as high surface area, diameter and pore volume. In this context, this paper proposed the adsorbent synthesis of MCM-41 modified type, aimed at removing naphthenic acid mixed model of jet fuel (n-dodecanoic acid in n-dodecane). The MCM-41, Sr-MCM- 41, La-MCM-41, Ce-MCM-41, Sr-La-MCM-41, Sr-Ce-MCM-41 adsorbents were synthesized by hydrothermal method and characterized by techniques thermogravimetric analysis (TGA), X-ray diffraction (XRD), N2 adsorption/desorption using the Brunauer, Emmett and Teller (BET) and Barrett, Joyner and Halenda (BJH) methods, spectroscopy in the infrared Fourier transform (FT-IR), scanning electron microscopy with energy dispersive spectroscopy X-ray (SEM/EDS) and pH of zero charge point (pHpzc). A study was conducted to check the adsorbent for use in adsorption studies. With the selected adsorbent, kinetic studies were performed and adsorption equilibrium finite bath system. From the data obtained, we evaluated the system continuous fixed bed and the cycles of adsorption/desorption. The hydrothermal method was effective as the results of the characterization analyzes, since after the incorporation of metals, materials maintained the pattern structure of MCM-41. From the PHpzc study it was found that the incorporation of the alkaline earth metal Sr increased basicity of all materials. The Sr-Ce-MCM-41 adsorbent has higher thermal stability and higher pore volume and pore diameter, also having a greater adsorption capacity. The kinetic study showed that equilibrium is reached after 420 minutes, with a capacity of 0.64 gac.g-1 ads and % removal of 82.5%. The adsorption isotherm presented type IV behavior and higher adsorptive capacity quantified in the studied concentration range was 0.8 gac.g-1 ads. The kinetic model of Langmuir-Freundlich and model of Brunauer, Emmett and Teller (BET) were satisfactory experimental data of adsorption kinetics and equilibrium in finite bath system. In the fixed bed system, the breakthrough time and saturation curve were affected by varying the flow rate and the bed of the feed concentration. The experimental data were fitted to the model of Langmuir-Freundlich, since the effects of mass transfer resistance and diffusion were discarded. Studies of adsorption/desorption indicated the possibility of naphthenic acid recovery aiming their subsequent use and application. The adsorbent studied Sr-Ce-MCM-41 has potential for the removal of naphthenic acids present in jet fuel model in the conditions studied.
37

On the bicyclic acids of petroleum

Wilde, Michael John January 2016 (has links)
The identification of petroleum acids, also known as ‘naphthenic’ acids (NA), has been an analytical challenge for over 140 years. However, most recent interest in NA has arisen due to concerns over their presence and apparent associated toxic effect in oil platform produced waters and oil sands process waters (OSPW), respectively. Understanding the toxicity, transformations during biodegradation and remediation treatments and predicting the fate of NA in the environment will be aided by the identification of individual NA. However the elucidation of individual acid structures by standard chromatographic techniques, such as GC-MS, has so far been limited by the extreme complexity of the NA mixtures. Recent analysis of NA as the methyl ester derivatives, by multidimensional gas chromatography-mass spectrometry (GC×GC-MS), has resulted in the identification of several tri- to pentacyclic, aromatic and sulphur-containing acids as well as tricyclic diacids. Therefore the current investigation focused on the identification of the abundant bicyclic acids in petroleum and OSPW acid extracts, utilising the unparalleled chromatographic separation and mass spectrometric detection offered by GC×GC-MS. Analysis of fractionated NA as methyl esters, resulted in the first identification of several bicyclic acids in OSPW including several novel bridged bicyclic acids, several fused bicyclic acids, as well as some terpenoid-derived drimane and labdane acids. However, identifications were limited somewhat by a lack of reference mass spectra and lack of availability of reference compounds for co-chromatography. A complementary method, based on an historical approach, involving reduction of NA esters to hydrocarbons, was modified and substantially improved. Analysis of the hydrocarbons resulting from the reduced acids, by GC×GC-MS, and comparison of the hydrocarbon mass spectra with the more abundant reference spectra available for petroleum hydrocarbons, resulted in the identification of over 40 individual bicyclic acids including fused, bridged and terpenoid-derived acids. The study provides the most comprehensive analysis of one of the major classes of NA (the bicyclic acids) to date. The methods developed were applied to the structural elucidation of NA in commercial NA and OSPW NA and resulted in the identification of numerous alicyclic, aromatic and sulphur-containing acids, supporting and extending previous identifications. There is clear potential for this method to be used for the identification of other unknown acids and functionalised biomarkers in complex matrices. The new knowledge of the acid structures in petroleum and OSPW NA can now be used to inform future research into the environmental monitoring and toxicity of NA.
38

Effects of Naphthenic Acids and Acid Extractable Organic Mixtures on Development of The Frog Silurana (Xenopus) Tropicalis

Gutierrez Villagomez, Juan Manuel 16 May 2018 (has links)
Naphthenic acids (NAs) are oil-derived mixtures of carboxylic acids and are aquatic contaminants of emerging concern. The objective of the research presented in this thesis was to investigate the toxicity of NAs in tadpoles of the frog Silurana (Xenopus) tropicalis. Using electrospray ionization high-resolution mass spectrometry (ESI-HRMS), I determined that the proportions of O2 (presumably carboxylic acid moiety) species were 98.8, 98.9 and 58.6% respectively, for two commercial extracts (S1 and S2), and acid extractable organics (AEOs) from oil sands process-affected water (OSPW). The rank order potency based on the lethal concentration fifty (LC50) and effect concentration fifty (EC50) with and without normalization for the quantity of O2 species was S1 > S2 > AEO. The main effects observed were reduced body size, edema, and cranial, cardiac, gut and ocular abnormalities. Oligonucleotide microarray technology was used to determine the transcriptomic responses in developing S. tropicalis embryos following exposure to S1 and S2 at a sub-lethal concentration of 2 mg/L. Some of the significantly enriched pathways (p < 0.05) included metabolism and cell membrane depolarization, and some were related to observed abnormalities including edema, gastrointestinal system, and cartilage differentiation. I established and validated a derivatization method for NAs using pentafluorobenzyl bromide (PFBBr) prior to gas chromatography-electron impact mass spectrometry (GC-EIMS) to increase chromatographic resolution, and sensitivity, compared to boron trifluoride-methanol (BF3/MeOH) and N-tert-Butyldimethylsilyl-N-methyltrifluoroacetamide (MTBSTFA). Solid-phase microextraction of volatiles originating from S1, S2, Merichem NAs and an AEO mixture led to the identification of 54, 56, 40 and 4 compounds, respectively. The compounds identified in the mixtures included aliphatic and cyclic hydrocarbons, carboxylic acids, alkyl-benzenes, phenols, naphthalene and alkyl-naphthalene, and decalin compounds. To determine the chemical nature of the toxic compounds in NA mixtures, the S2 and AEOs preparations were fractionated using open column chromatography. A non-polar and a polar fraction were obtained from S2. Overall, the toxicity of the polar fraction was not significantly different from whole S2 (p > 0.05). Six fractions of AEOs were obtained, however because of limited material, only the toxicities of F3 and F4 were assessed. The toxicity of F3 was significantly lower than AEOs (p < 0.05) and F4 was not toxic for S. tropicalis (p > 0.05). These results suggest that during fractionation, toxic compounds were lost or that the toxicity of AEOs results from the combined effects of the compounds present in the whole extract. The toxicological dose descriptors, morphometric, transcriptomic and chemical analysis herein presented may contribute to the development of environmental guidelines for NAs and AEOs.
39

Izolovanje, strukturna karakterizacija i biološka aktivnost naftnih kiselina iz Vojvođanske nafte / Isolatin, structural characterization and biological activity of naphthenic acids from Vojvodina oil

Grbović Ljubica 04 December 2009 (has links)
<p>Grupno-strukturna analiza naftnih kiselina izolovanih iz srednjih uljnih&nbsp;komercijalnih frakcija vojvođanske nafte &bdquo;Velebit&rdquo; rađena je analizom IR-,&nbsp;<sup>1</sup>H- i&nbsp;<sup>13</sup>C NMR- i ESI-MS spektara niske rezolucije. Određeno je &scaron;est klasa&nbsp;karboksilnih kiselina op&scaron;te molekulske formule C<sub>n</sub>H<sub>2n-Z</sub>O<sub>2</sub>. To su karboksilne&nbsp;kiseline u opsegu masa 240-466 sa 15-31 C atoma u molekulu koje su&nbsp;grupisane u pet cikloalkil Z-serija: monociklična- (C<sub>n</sub>H<sub>2n-2</sub>O<sub>2</sub>, 14.72%),&nbsp;biciklična- (C<sub>n</sub>H<sub>2n-4</sub>O<sub>2</sub>, 34.63%), triciklična- (C<sub>n</sub>H<sub>2n-6</sub>O<sub>2</sub>, 25.03%), tetraciklična- (C<sub>n</sub>H<sub>2n-8</sub>O<sub>2</sub>, 10.04%), pentaciklična klasa karboksilnih kiselina (C<sub>n</sub>H<sub>2n-10</sub>O<sub>2</sub>, 4.99%) i jedna alkanska klasa kiselina sa alkil grupama otvorenog niza (C<sub>n</sub>H<sub>2n</sub>O<sub>2</sub>, 10.57%).</p><p>Razdvajanjem na bazi različite kiselosti i njihove rastvorljivosti u vodi na&nbsp;određenim pH vrednostima u rasponu od pH 2-10 dobijeno je devet užih&nbsp;frakcija kiselina. Ekstrakcijom sa etrom u vodi nerastvornih kiselina u rasponu&nbsp;od po jedne pH jedinice dobijena je sledeća distribucija masa: 9.57% (pH 10),&nbsp;12.69% (pH 9), 5.91% (pH 8), 4.85% (pH 7), 2.44% (pH 6), 11.71% (pH 5),&nbsp;23.94% (pH 4), 16.76% (pH 3) i 10.12% (pH 2). Razdvajanjem kiselina na bazi&nbsp;njihove kiselosti oko 50% mase kiselina ekstrahovano je od pH 2-4, znači u&nbsp;grupi jačih kiselina. Masenom spektrometrijom niske rezolucije ESI-MS na&nbsp;pH 4 vidi se da su u sme&scaron;i kiselina skoncentrisane kiseline sa vi&scaron;e prstenova u&nbsp;alkilnom delu sa maksimumom na tricikličnim kiselinama (36.50%), dok su&nbsp;pojedinačno najzastupljenije tetraciklične strukture kiselina C<sub>20</sub>H<sub>32</sub>O<sub>2</sub>(4.43%) i&nbsp;C<sub>21</sub>H<sub>34</sub>O<sub>2</sub>(4.56%). Na pH 8 biciklične- i triciklične strukture su zastupljene&nbsp;ukupno sa 65.02% sa maksimalno zastupljenim kiselinama sa 20-26 C atoma&nbsp;u molekulu, a izdvajaju se C<sub>22</sub>H<sub>38</sub>O<sub>2</sub> (5.26%)&nbsp;biciklične- i C<sub>24</sub>H<sub>42</sub>O<sub>2</sub>(7.01%)&nbsp;triciklične strukure, a od tetracikličnih struktura kiselina izdvaja se C<sub>24</sub>H<sub>40</sub>O<sub>2&nbsp;</sub>(4.77%). Na pH 10 najzastupljenije izolovane kiseline su aciklične, odnosno&nbsp;masne kiseline zastupljene sa 25.28%, a najdominantnije su strukture&nbsp;C<sub>21</sub>H<sub>42</sub>O<sub>2</sub> (4.83%), dok su ostale klase kiselina ujednačene po svom masenom&nbsp;udelu u odnosu na sastav u ukupnoj polaznoj sme&scaron;i kiselina.&nbsp;Drugi deo rada obuvata derivatizaciju izolovanih prirodnih naftnih kiselina.&nbsp;Sintetizovani su funkcionalni kiseonični metil-, etil-, n-butil-,&nbsp; terc-butil- i&nbsp;benzil-derivati naftnih kiselina kao i funkcionalni azotni derivati: amidi i anilidi&nbsp;naftnih kiselina. Sinteze navedenih estara rađene su klasičnim postupcima i&nbsp;modifikovanom metodom esterifikacije u kiselo-katalizovanim uslovima&nbsp;upotrebom mikrotalasa kao ko-katalizatora, &scaron;to je imalo za cilj skraćenje&nbsp;reakciong vremena i pobolj&scaron;anje ekolo&scaron;kih sintetskih uslova.<br />Modifikacijom sinteze metilnaftenata MT-zagrevanjem 48 puta je skraćeno&nbsp;vreme trajanja sinteze, prinosi ni promenom reakcionih parametara (vreme,&nbsp;snaga MT) nisu bitno promenjeni. Strukturnom analizom ESI-MS spektra&nbsp;polaznih kiselina i metilnaftenata dobijenih metilovanjem naftnih kiselina&nbsp;utvrđeno je da je odnos klasa u dobroj podudarnosti. Prinos estara u ovoj&nbsp;sintezi je 95.47%. Esterifikacija naftnih kiselina etil alkoholom rađena je u&nbsp;uslovima kisele katalize uz konvencionalno zagrevanje (91.76%), a&nbsp;modifikacijom metode MT-zagrevanjem (150 W) reakciono vreme je skaćeno&nbsp;96 puta (92.19%). Esterifikacija naftnih kiselina n-butil alkoholom rađena je uz&nbsp;sumpornu kiselinu kao katalizator i uz konvencionalno zagrevanje (94.24%), a&nbsp;u uslovima MT-zagrevanja (150 W) 72 puta je skraćeno reakciono vreme&nbsp;(61.15%). Sinteza terc-butilnaftenata rađena je prevođenjem naftnih kiselina u&nbsp;hloride a zatim reakcijom sa terc-butil alkoholom nastaju terc-butilnaftenati&nbsp;(80.17%). Modifikovanom metodom klasične reakcije esterifikacije naftnih&nbsp;kiselina terc-butil alkoholom katalizovanom sumpornom kiselinom u uslovima&nbsp;MT-zagrevanja (150 W) ostvaren je prinos od 85.49% a vreme trajanja reakcije&nbsp;je 5 minuta. Sinteza benzilnaftenata rađena je prevođenjem naftnih kiselina u&nbsp;hloride a zatim reakcijom sa benzil alkoholom nastaju benzilnaftenati&nbsp;(84.43%), a modifikovanom metodom klasične kiselo-katalizovane&nbsp;esterifikacije naftnih kiselina benzil alkoholom u uslovima MT-zagrevanja&nbsp;(150 W) ostvaren je prinos od 85.49% uz reakciono vreme od 5 minuta.&nbsp;Sinteza amida naftnih kiselina rađena je iz hlorida reakcijom sa amonijakom.&nbsp;Prinos čistih amida je 65.74%, a reakcija amidacije sa amonijakom trajala je&nbsp;15 minuta. Strukturnom analizom ESI-MS spektra amida naftnih kiselina&nbsp;utvrđen je grupno-strukturni sastav amida. Među strukturama amida naftenskih&nbsp;kiselina takođe su dominantne biciklične- i triciklične strukture, kao i u sme&scaron;i&nbsp;slobodnih kiselina. Sinteza anilida naftnih kiselina rađena je iz hlorida reakcijom sa anilinom. Prinos čistih anilida je 96.48%, a reakcija amidacije anilinom trajala je 30 minuta. Strukturnom analizom ESI-MS spektra anilida naftnih kiselina utvrđen je grupno-strukturni sastav proizvoda, anilida. Među strukturama anilida naftenskih kiselina takođe su dominantne biciklične- i triciklične strukture kao i u sme&scaron;i slobodnih kiselina.</p><p>U trećem delu ovog rada ispitivana je biolo&scaron;ka aktivnost naftnih kiselina&nbsp;auksinskog i giberelinskog tipa, njihov uticaj na ožiljavanje reznica,&nbsp;ukorenjivanje bočnih grana i mikroizdanaka biljaka, na aktivnost biljnih&nbsp;hormona, kao i na usvajanje metalnih jona kod biljaka.&nbsp;</p><p>Aktivnost naftenskih kiselina utvrđena je pomoću tri in vitro&nbsp; biolo&scaron;ka testa.&nbsp;&bdquo;Koleoptil test&rdquo;, rađen je na dva supstrata, odnosno na semenu ozime p&scaron;enice&nbsp;novosadske sorte Partizankai jare p&scaron;enice takođe novosadske sorte Venera.&nbsp;Referentna aktivnost u testu rađena je sa -naftilsirćetnom 3-indolsirćetnom&nbsp;kiselinom. U oba testa ustanovljen je približno isti odnos aktivnosti rastvora&nbsp;naftenskih kiselina i aktivnosti standardnih biljnih hormona. &bdquo;Test inhibicije&nbsp;klijanja&rdquo; semena rađen je sa semenom crne slačice, Brasscia nigra. Najveći&nbsp;uticaj naftenskih kiselina na inhibiciju klijanja postignut je u rasponu&nbsp;koncentracija kiselina od 10<sup>-7</sup>&nbsp;-10<sup>-8&nbsp;</sup>mol/L (0.05-0.01 mg/L). Testovi za &scaron;est užih&nbsp;frakcija dobijenih iz sme&scaron;e ukupnih kiselina razdvajanjem na bazi različite&nbsp;rastvorljivosti pri različitim pH vrednostima pokazuju istu aktivnost kao&nbsp;3-indolsirćetna kiselina (0.5 mg/L), a da je frakcija izdvojena iz vodenog&nbsp;rastvora na pH 7 takođe aktivna ali u poređenju sa 3-indolsirćetnom kiselinom&nbsp;to je 10 puta niža aktivnost. Hormonska aktivnost giberelenskog tipa ispitivanih&nbsp;kalijumovih soli naftenskih kiselina utvrđena je &bdquo;Endosperm testom&rdquo;, u kojem je&nbsp;određivana aktivnost amilaze spektrofotometrijskim praćenjem povećanja&nbsp;koncentracije redukujućih &scaron;ećera u endospermu semena tretiranog ječma i&nbsp;poređena sa aktivno&scaron;ću rastvora giberelinske kiseline (GA3). Rezultati ovih&nbsp;testova pokazuju da delovanjem vodenih rastvora užih frakcija naftenskih&nbsp;kiselina u koncentraciji 1.0 mg/L (3.5 x 10<sup>-6 </sup>mol/L)frakcija izolovana pri pH 8&nbsp;ima aktivnost koja je približno u opsegu aktivnosti giberelina koncentracije&nbsp;10<sup>-2</sup>-10<sup>-3&nbsp;</sup>mg/L.&nbsp;</p><p>Natrijum-naftenati u koncentraciji od 10<sup>-6&nbsp;</sup><br />do 10<sup>-8&nbsp;</sup>mol/L stimuli&scaron;u formiranje&nbsp;adventivnih korenova kod reznica suncokreta pa je broj korenova po biljci 40&nbsp;puta veći kod biljaka koje su bile potopljene u rastvor natrijum-naftenata u&nbsp;odnosu na one koje su bile potopljene u vodu, a sličan efekat utvrđen je i pri&nbsp;tretiranju bočnih grana suncokreta.&nbsp;</p><p>Ožiljavanje drvenastih biljaka rađeno je na reznicama bele topole (Populus&nbsp;alba) i reznicama američke crne topole (Populus deltoides). Uočen je jasan&nbsp;inhibitomi efekat na rast korenčića i izbojka u vodenom medijumu sa 10<sup>-4&nbsp;</sup>mol/L&nbsp;naftenskih kiselina, dok je tretman od 24 časa doprineo većem broju korenčića&nbsp;na donjih 5 cm reznice, kao i ukupnog broja korenčića nego kod kontrole.&nbsp;</p><p>U testu ukorenjivanja mikroizdanaka kod hrizantema najveći broj korenova&nbsp;dobijen je nakon tretmana sa rastvorom koji sadrži 10 &micro;mol/L ukupnih naftenata&nbsp;i tretmanom sa 50 &micro;mol/Lfrakcijom kiselina izolovanom pri pH 7. Oba rezultata&nbsp;su na nivou aktivnosti 3-indolbuterne kiseline koncentracije 10 &micro;mol/L&scaron;to znači&nbsp;da u ovom slučaju frakcionacija nije neophodna.&nbsp;</p><p>Efekti natrijum-naftenata na ukorenjivanje praćeni su merenjem nivoa totalnih&nbsp;peroksidaza i amilaze, &nbsp;kao i sadržaja redukujućih &scaron;ećera i ukupnih proteina u&nbsp;bazalnim delovima reznica bagrema(Rozaszin-AC).&nbsp; Nakon 1; 3 i 6 dana&nbsp;reznice su uzete za biohemijske analize. U svakom slučaju, aktivnosti&nbsp;IAA-oksidaze i amilaze su se povećavale do trećeg dana, &nbsp;a zatim smanjuje.&nbsp;Efekat je bio jače izražen posle tročasovnog tretmana sa natrijum-naftenatima&nbsp;u poređenju sa &scaron;estočasovnim tretmanom i kontrolom. Sadržaj rastvornih&nbsp;proteina je bio povećan jedan dan posle tretmana, smanjen trećeg i ponovo povećan &scaron;estog dana, osim za &scaron;estočasovni tretman natrijum-naftenatima, kada je efekat bio sasvim suprotan.</p><p>Test uticaja naftnih kiselina na nivo kadmijuma u biljkama pokazuje fiziolo&scaron;ko delovanje naftnih kiselina na snižavanje nivoa te&scaron;kih metala u biljci, u ovom slučaju kadmijuma. Ispitivan je efekat niske koncentracije natrijum-naftenata (10<sup>-7&nbsp;</sup>mol/L) na ukupan sadržaj Cd u pojedinim frakcijama interćelijskog prostora kao i unutar ćelija, kao i na neke fiziolo&scaron;ke i biohemijske parametre kod mladih biljaka soje koje su uzgajane u prisustvu kadmijum-hlorida koncentracije 1 mmol/L. Prisustvo naftenata smanjuje sadržaj ukupnog kadmijuma kako u korenu tako i u stablu i listovima u proseku za oko 40% i ublažava &scaron;tetne efekte kadmijuma na aktivnost nitrat-reduktaze kao i na sadržaje fotosintetskih pigmenata.</p><p>Tretman biljaka niskim koncentracijama natrijum-naftenata utiče na&nbsp;akumulaciju nekih esencijalnih elemenata kod mladih biljaka soje. Prisustvo&nbsp;naftenata (10<sup>-7 &nbsp;</sup>mol/L) značajno povećava sadržaj Mn, Fe, Zn i Ni u korenu, ali&nbsp;u stabljici i listovima samo sadržaj Fe i Mn. U korenu, sadržaj Mn je četiri puta&nbsp;veći a sadržaji Fe, Zn i Ni su povećani 17%, 60% i 68%, respektivno.&nbsp;</p><p>Ispitivanja na celeru i mrkvi su potvrdila da uticaj naftenata na mineralnu&nbsp;ishranu zavisi od primenjenog elementa i da je način preuzimanja određenih&nbsp;jona različit, &scaron;to ima za posledicu ili povećanje ili smanjenje sadržaja pojedinih&nbsp;jona u nekim delovima biljaka. Mlade biljke celera i mrkve, gajene u hranljivom&nbsp;medijumu, tretirane su natrijumovim solima naftenskih kiselina (10<sup>-7&nbsp;</sup>mol/L)&nbsp;folijarno ili prisustvom u hranljivom medijumu. Jedino je tretman putem&nbsp;prisustva naftenata u hranljivom medijumu smanjio svežu masu korena i&nbsp;nadzemnog dela oko 20% kod obe biljke.Oba tretmana uticala su na sadržaj&nbsp;Fe, Cu, Mn, Mg i Ca kod biljaka celera i Fe, Mn, Zn i Na kod biljaka mrkve.&nbsp;Kod biljaka celera do&scaron;lo je do smanjenja sadržaja navedenih nutrienata dok je&nbsp;u korenu biljaka mrkve do&scaron;lo do povećanja sadržaja Fe za 45%, Mn za 70% i&nbsp;Zn za 37%. Kod ovih biljaka prisustvo naftenata u hranljivom medijumu dovelo&nbsp;do smanjenja mase korenova i nadzemnih delova, &scaron;to je potpuno suprotno od&nbsp;rezultata dobijenih kod biljaka soje.&nbsp; Folijarnim tretmanom je značajno<br />povećana masa nadzemnog samo kod celera.</p> / <p>Group-structural analysis of naphthenic acids isolated from middle&nbsp;commercial fractions of Vojvodina oil &bdquo;Velebit&rdquo; was performed with the&nbsp;analysis of IR-,<br /><sup>1</sup>H- and&nbsp;<sup>13</sup>C NMR- and ESI-MS low resolution spectrums.&nbsp;Six classes of carboxylic acids of the general molecular formula C<sub>n</sub>H<sub>2n-Z</sub>O<sub>2&nbsp;</sub>were determined. These are carboxylic acids with mass range of 240-466&nbsp;with 15-31 C atoms in molecule which are grouped in five cycloalkyl&nbsp;<span style="font-size: 12px;">Z-series: monocyclic- (C<sub>n</sub>H<sub>2n-2</sub>O<sub>2</sub>, 14.72%), bicyclic- (C<sub>n</sub>H<sub>2n-4</sub>O<sub>2</sub>, 34.63%),&nbsp;</span><span style="font-size: 12px;">tricyclic- (C<sub>n</sub>H<sub>2n-6</sub>O<sub>2</sub>, 25.03%), tetracyclic- (C<sub>n</sub>H<sub>2n-8</sub>O<sub>2</sub>, &nbsp;10.04%), pentacyclic&nbsp;</span><span style="font-size: 12px;">class of carboxylic acids (C<sub>n</sub>H<sub>2n-10</sub>O<sub>2</sub>, 4.99%) and one alyphatic class of&nbsp;</span><span style="font-size: 12px;">acids with open chain alkyl groups (C<sub>n</sub>H<sub>2n</sub>O<sub>2</sub>, 10.57%).</span></p><p>By fractioning on the basis of different levels of acidity and their solubility in&nbsp;water with pH values ranging from pH 2-10 nine subfractions of acids were&nbsp;obtained. By extraction with ether in water undissolved acids in the range of&nbsp;one pH unit the following distribution of mass was performed: 9.57%&nbsp;(pH 10), 12.69% (pH 9), 5.91% (pH 8), 4.85% (pH 7), 2.44% (pH 6), 11.71%&nbsp;(pH 5), 23.94% (pH 4), 16.76% (pH 3) and 10.12% (pH 2). By fractioning&nbsp;acids on the basis of their acidity about 50% of acid &nbsp;mass was extracted at&nbsp;pH 2-4, i.e., in the group of stronger acids. Low resolution mass&nbsp;spectrometry ESI-MS shows that at pH 4 acids with more rings in the alkyl&nbsp;<br />section were concentrated in the mixture with maximum at tricyclic acids&nbsp;(36.50%), while individually tetracyclic acid structures C<sub>20</sub>H<sub>32</sub>O<sub>2</sub> (4.43%) and&nbsp;C<sub>21</sub>H<sub>34</sub>O<sub>2&nbsp;</sub>(4.56%) were most prominent. At pH 8 bicyclic- and tricyclic&nbsp;structures are represented &nbsp;together by 65.02% with acids with 20-26 C&nbsp;atoms in molecule being represented the most, and C<sub>22</sub>H<sub>38</sub>O<sub>2</sub>&nbsp; (5.26%)&nbsp;bicyclic- and C<sub>24</sub>H<sub>42</sub>O<sub>2</sub>(7.01%) tricyclic structures stand &nbsp;out, while with&nbsp;tertacyclic acid structures C<sub>24</sub>H<sub>40</sub>O<sub>2</sub> (4.77%) stands out. At pH 10 most&nbsp;represented isolated acids are acyclic, i.e., fatty acids which are&nbsp;represented by 25.28%, with the most dominant C<sub>21</sub>H<sub>42</sub>O<sub>2&nbsp;</sub>structures&nbsp;(4.83%), while the other classes &nbsp;of acids are well balanced in their mass&nbsp;share in relation to the composition of the overall initial acid mixture.</p><p>The second part of this work deals with derivatization of the isolated natural&nbsp;naphthenic acids. Functional oxygen methyl-, ethyl-, n-butyl-, tert-butyl and&nbsp;benzyl-derivatives of naphthenic acids as well as functional nitrogen&nbsp;derivatives: amides and anilides of naphthenic acids were synthesized. The&nbsp;syntheses of the above mentioned esters were performed by conventional&nbsp;methods and by a modified method of esterification in acid-catalyzed&nbsp;conditions using microwaves as a co-catalyst with the aim of shortening the&nbsp;reaction time and improving the ecological synthetic conditions.&nbsp;</p><p>By modification of methyl naphthenates synthesis using MT-heating the&nbsp;time period for synthesis is reduced 48 times and the yield does not&nbsp;significantly change even after the reaction parameters (time, MT power)&nbsp;have been altered. Using structural analysis of ESI-MS spectrum of initial&nbsp;carboxylic acids and the methyl naphthenates obtained through methylation&nbsp;of naphthenic acids it was establishedthat the class ratio shows great&nbsp;compatibility. The esters yield in this synthesis is 95.47%. The esterification&nbsp;of naphthenic acids with ethyl alcohol done under the conditions of acid&nbsp;catalysis with conventional heating (91.76%), and with the modified method&nbsp;MT-heating (150 W) the reaction time is reduced 96 times (92.19%). The&nbsp;esterification of naphthenic acids with n-butyl alcohol was performed using&nbsp;sulphuric acid as a catalyst with conventional heating (94.24%), and under&nbsp;MT-heating conditions (150 W) reaction time was 72 times&nbsp; shorter&nbsp;(61.15%). The synthesis of&nbsp; tert-butyl naphthenates was performed by&nbsp;conversion of naphthenic acids into chlorides, followed by the reaction with&nbsp;tert-butyl alcohol which resulted in tert-butyl naphthenates (80.17%). By the&nbsp;modified method of conventional reaction of esterification of naphthenic&nbsp;acids using tert-butyl alcohol catalysed with sulphuric acid in MT-heating&nbsp;conditions (150 W) the yield was 85.49% and reaction time was 5 minutes.&nbsp;The synthesis of benzyl naphthenates was performed by conversion of&nbsp;naphthenic acids into chlorides, followed by a reaction with benzyl alcohol&nbsp;which produces benzyl naphthenates (84.43%), whereas the modified&nbsp;method of conventional acid-catalysed esterification of naphthenic acids&nbsp;using benzyl alcohol under MT-heating (150 W) conditions the yield was&nbsp;85.49% with the reaction time of 5 minutes.&nbsp;</p><p>The synthesis of naphthenic acid amides was done from chlorides by&nbsp;reaction with ammonia. The yield of pure amides was 65.74%, and the&nbsp;reaction of amidation with ammonia lasted for 15 minutes. The structural&nbsp;analysis of ESI-MS spectrum of naphthenic acid amides determined the&nbsp;group-structural composition of amides. With the structures of amides of&nbsp;naphthenic acids bicyclic- and tricyclic structures are also dominant, as in&nbsp;the mixture of free acids. The synthesis of naphthenic acid anilides were&nbsp;performed from chloride by reacting with aniline. The yield of pure anilides&nbsp;<br />was 96.48%, and the reaction of amidatation lasted for 30 minutes. The&nbsp;structural analysis of ESI-MS spectrum of naphthenic acid anilides&nbsp;determined the group-structural composition of anilide products. With the&nbsp;structures of anilides of naphthenic &nbsp;acids bicyclic- and tricyclic structures&nbsp;are also dominant, as in the mixture of free acids.</p><p>The third part of this work tests the biological activity of naphthenic acids of&nbsp;auxine and gibberellinic type, their influence on the rooting of cuttings,&nbsp;lateral branches and microshoots of plants, on the activity of plant&nbsp;hormones as well as on the metal ions uptake by plants.&nbsp;</p><p>The activity of naphthenic acids was determined using three in vitro&nbsp;biological tests. &bdquo;Koleoptil test&rdquo;, was done on two substrates, namely the&nbsp;seed of winter wheat of the Partizankasort and the spring wheat of the&nbsp;Venerasort. The referential activity in the test was performed with&nbsp;&alpha;-naphthylacetic- and 3-indolacetic acid. Both tests showed approximately&nbsp;the same ratio of activity of naphthenic acid solutions and standard plant&nbsp;hormones. &bdquo;Germination Inhibition Test&rdquo; of the seed was performed using&nbsp;<br />Brasscia nigraseed. The greatest influence of naphthenic acids to&nbsp;germination inhibition was achieved in the acid concentration ranging from&nbsp;10<sup>-7</sup>-10<sup>-8&nbsp;</sup>mol/L (0.05-0.01 mg/L). The tests for six narrow fractions obtained&nbsp;from the overall mixture of acids through fractioning on the basis of different&nbsp;solubility at different pH values show the same activity as 3-indolacetic acid&nbsp;(0.5 mg/L), with the fraction isolated from the aqueous solution at pH 7 also&nbsp;active but in comparison to 3-indolacetic acid this activity was 10 times&nbsp;lower. Hormone activity of gibberellinic type of the potassium salts of&nbsp;naphthenic acids was determined using &ldquo;Endosperm Test&rdquo; where amylase&nbsp;<br />activity was determined by spectrophotometric measuring of the increase of&nbsp;the concentration of reducing sugars in endosperm in the treated barley&nbsp;seed which was then compared to the activity of the gibberellic acid solution&nbsp;(GA3).&nbsp; The results of these tests indicate that the activity of aqueous&nbsp;solutions of narrow fractions of naphthenic acids in the concentration of&nbsp;1.0 mg/L (3.5 x 10<sup>-6&nbsp;</sup>mol/L)the fraction isolated &nbsp;at pH 8 has the activity&nbsp;which is approximately within the range of activities of gibberellin of the&nbsp;concentration of 10<sup>-2</sup>-10<sup>-3&nbsp;</sup>mg/L.&nbsp;</p><p>Sodium salts of naphthenic acids in concentrations of 10<sup>-6&nbsp;</sup>do 10<sup>-8&nbsp;</sup>mol/L&nbsp;stimulated formation of adventitious roots in&nbsp;<span style="font-size: 12px;">sunflower cuttings even by a&nbsp;</span><span style="font-size: 12px;">factor of 40 compared with control, the effect being also observed lateral&nbsp;</span><span style="font-size: 12px;">branches of interspecies sunflower hybrids. The obtained results suggest&nbsp;</span><span style="font-size: 12px;">the possibility of using naphthenic acids as a means for rooting of plant&nbsp;</span><span style="font-size: 12px;">cuttings.</span></p><p>Rooting of hardwood plants was investigated on the cuttings of white poplar&nbsp;(Populus alba) and black poplar (Populus deltoides). The distinct inhibitory&nbsp;effect on the root and shoot growth in water culture was detected in the&nbsp;concentration of naphtenic acids 10<sup>-4&nbsp;</sup>mol/L, but 24-hour treatment raised&nbsp;the number roots on undermost 5 cm of the cutting, as well as the total&nbsp;number of roots, comparing to the control.</p><p>In the test of rooting microshoots ofchrysanthemum the highest number of&nbsp;<span style="font-size: 12px;">roots was achieved after the treatment with solution containing 10 &micro;mol/L of&nbsp;</span><span style="font-size: 12px;">total napthenates, as &nbsp;well as after the treatment with fraction of naphthenic&nbsp;</span><span style="font-size: 12px;">acids which was isolated at pH &nbsp;7 in concentration of 50 &micro;mol/L. Both results&nbsp;</span><span style="font-size: 12px;">are on the level of activity of 3-ndolbutyric acid in concentration of 10 &micro;mol/L&nbsp;</span><span style="font-size: 12px;">which suggests that in this case ractionation is not necessary.</span></p><p>The effects of sodium naphthenates on rooting were investigated by&nbsp;measuring the level of total peroxidases and amylase, along with the&nbsp;contents of reducing sugars and total proteins in basal parts of cuttings of&nbsp;black locust (Rozaszin-AC). After 1; 3 and 6 days cuttings were taken for&nbsp;biochemical analysis. In all cases, the activities of IAA-oxidase and amylase&nbsp;increased to the third day and showed a decrease afterwards. The effect&nbsp;was more pronounced after the three-hour treatment with sodium&nbsp;naphthenates, compared to the six-hour treatment and control. The content&nbsp;of soluble proteins increased one dayafter the treatment and decreased to&nbsp;the third and again increased to the sixth day, an exception being the&nbsp;six-hour treatment with sodium naphthenate, when the effect was&nbsp;completely opposite.</p><p>The test of naphthenic acids influence on the level of cadmium in plants&nbsp;showed physiological activity of naphthenic acids on the decrease of the&nbsp;level of heavy metals, &nbsp;in this case cadmium, in the plant. The effect of low&nbsp;concentrations (10<sup>-7&nbsp;</sup>mol/L) of sodium naphthenate on total content of Cd in&nbsp;the intercellular space and inside cells, as &nbsp;well as on some physiological&nbsp;and biochemical parameters of young soybean plants grown in the&nbsp;presence of 1 mmol/L solution of cadmium chloride was investigated.&nbsp;Presence of naphthenate reduced in average by 40 % content of total and&nbsp;intracellular Cd in root, stem and leaves and alleviated the harmful effect of&nbsp;<br />Cd on activity of nitrate reductase and content of photosynthetic pigments.</p><p>Treatment of soybean plants with low concentrations of sodium&nbsp;naphthenate influenced the accumulation ofsome essential elements by the&nbsp;young plants. The presence of naphthenates (10<sup>-7&nbsp;</sup>mol/L) significantly&nbsp;increased content of Mn, Fe, Zn and Ni in root, but in stem and leaves&nbsp;increased only contents of Fe and Mn. Inroot, the content of Mn increased&nbsp;four times while contents of Fe, Zn and Ni increased by 17%, &nbsp;60% and 68%&nbsp;respectively compared to the control.</p><p>Investigations on celery and carrot&nbsp; confirmed that the influence of&nbsp;naphthenates on mineral nutrition depends on the applied element and that&nbsp;the way of uptake of certain ions is different, which results in either increase&nbsp;or decrease of the contents of some ions in certain parts of plants. Young&nbsp;plants of celery and carrot, were grown in the nutrient medium and treated&nbsp;with sodium salts of naphthenic acids (10<sup>-7&nbsp;</sup>mol/L) over the leaves or with its&nbsp;presence in the nutrient medium. Only the treatment based on the &nbsp;presence&nbsp;of naphthenates in the nutrient medium resulted in the decrease of the fresh&nbsp;mass of root and aboveground part by about 20% for both plants. Both&nbsp;treatments had influence on the content of Fe, Cu, Mn, Mg and Ca in the&nbsp;plants of celery and Fe, Mn, Zn and Na in the plants of carrots. In the plants&nbsp;of celery the content of the mentioned nutrients was decreased, while in the&nbsp;root of plants of carrot &nbsp;the content was increased, Fe by 45%, Mn by 70%&nbsp;and Zn by 37%. With these plants &nbsp;the presence of naphthenates in the&nbsp;nutrient medium caused the reducing roots and aboveground parts, which is&nbsp;completely opposite from the results obtained with soybean plants. The&nbsp;treatment by leaves significantly increased the mass of aboveground part&nbsp;only with celery.</p>
40

Mikrotalasno stimulisane transformacije prirodnih i sintetičkih karboksilnih kiselina i njihovih derivata / Microwave-assisted transformation of natural and synthetic carboxylic acids and their derivatives

Pavlović Ksenija 25 September 2014 (has links)
<p>Predviđena istraživanja u ovoj doktorskoj disertaciji su usmerena u pravcu&nbsp;<br />modifikacije klasičnih metoda i postupaka za transformaciju karboksilne grupe&nbsp;<br />prirodnih i sintetičkih karboksilnih kiselina. Modifikacije su rađene novim,&nbsp;<br />savremenim, ekonomski i ekolo&scaron;ki opravdanim metodama rada u&nbsp;<br />mikrotalasnom reaktoru. Modifikovanim sintetskim postupcima u&nbsp;<br />mikrotalasnom reaktoru urađena je sinteza amida, hidroksamskih&nbsp; derivata,&nbsp;<br />kao i redukcija individualnih naftnih kiselina i&nbsp; sme&scaron;e&nbsp; prirodnih naftnih kiselina&nbsp;<br />&bdquo;Velebit&ldquo; do alkohola. Prirodne naftne kiseline kori&scaron;ćene u ovom radu su prvo&nbsp;<br />izolovane iz gasne frakcije (interval destilacije 168-290 &deg;C) vojvođanske nafte&nbsp;<br />&bdquo;Velebit&ldquo; a potom preči&scaron;ćene i razdvojene na uže frakcije na osnovu različite&nbsp;<br />kiselosti. Nakon toga, izvr&scaron;ena je njihova karakterizacija GC-MS-EI analizom&nbsp;<br />(čime je potvrđeno da dolazi do strukturne diferencijacije kiselina). U radu je&nbsp;<br />takođe ispitana biolo&scaron;ka aktivnost sintetizovanih derivata. Proučavan je uticaj&nbsp;<br />prirodnih naftnih kiselina &bdquo;Velebit&ldquo; i njenih derivata na rast&nbsp; pet sojeva&nbsp;<br />Pseudomonas sp., kao i uticaj odabranih sintetisanih jedinjenja na proliferaciju&nbsp;<br />četiri ćelijske linije humanih tumora pri čemu je kao kontrola služila jedna&nbsp;<br />zdrava humana ćelijska linija.</p> / <p>The investigation of this doctoral dissertation is directed toward the modification of the &nbsp;transformation of the carboxylic group of natural and synthetic carboxylic acids. The dissertation takes into consideration the classical methods and procedures of the reaction and modifies them using microwave reactor. The synthesis of amides, hydroxamic derivatives, as well as the reduction&nbsp; of individual petroleum acids and acid mixtures of natural oil &quot;Velebit&quot; to alcohol were achieved&nbsp; by the modifications made to the synthetic methods in the microwave reactor. The natural oil acids used within this study were first isolated from the gas fraction (distillation interval 168-290 &deg;C) of the Vojvodina&#39;s crude oil &quot;Velebit&quot;, and then purified and separated by the narrow fractions under the different acidity. After that, their characterisation was made by the GC-MS-EI analysis which confirmed that the structural differentiation of&nbsp;&nbsp; acids had been achieved. Also, the biological activity of the synthesized derivatives are analysed. The impact of natural petroleum acids &quot;Velebit&quot; and its derivatives on the growth of five strains of&nbsp; Pseudomonas&nbsp; sp. was studied, as well as the impact of selected synthesized compounds on the proliferation of four human tumor cell lines wherein one healthy human cell lines used as the control.</p>

Page generated in 0.0497 seconds