996 resultados para mature oil fields


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The study was done to identify the most active fungitoxic component of cinnamon bark (Cinnamomum zeylanicum) oil that can be used as a marker for standardization of cinnamon extract or oil based natural preservative of stored seeds. Aspergillus flavus and A. ruber were used as test fungi. The hexane extracted crude oil and the hydro-distilled essential oil from cinnamon bark had complete growth inhibition concentration (CGIC) of 300 and 100 µl/l, respectively. Both oils produced three fractions on preparative thin layer silica-gel chromatography plates. The fraction-2 of either oil was the largest and most active, with CGIC of 200 µl/l, but the fungitoxicity was also retained in the other two fractions. The fraction-1 and 3 of the crude oil reduced growth of both the fungal species by 65%, and those of distilled oil by 45% at 200 µl/l. The CGIC of these fractions from both the sources was above 500 µl/l. The gas chromatography and mass spectrometry (GC-MS) of the fraction-2 of the hexane extract revealed that it contained 61% cinnamaldehyde, 29% cinnamic acid, and two minor unidentified compounds in the proportion of 4% and 6%. The GC-MS of the fraction-2 of the distilled oil revealed that it contained 99.1% cinnamaldehyde and 0.9% of an unidentified compound. The CGIC of synthetic cinnamaldehyde was 300 µl/l and that of cinnamic acid above 500 µl/l. The 1:1 mixture of cinnamaldehyde and cinnamic acid had CGIC of 500 µl/l. The data revealed that cinnamaldehyde was the major fungitoxic component of hexane extract and the distilled essential oil of cinnamon bark, while other components have additive or synergistic effects on total fungitoxicity. It is suggested that the natural seed preservative based on cinnamon oil can be standardized against cinnamaldehyde.

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The virulence pattern of the isolates of Pyricularia grisea from commercial fields of the upland rice (Oryza sativa) cultivars 'Primavera' and 'BRS Bonança' was analyzed. A hundred and seventy monoconidial isolates of the pathogen virulent to 'Primavera' and 139 to 'BRS Bonança' collected from eight fields, during two years (2001-2003) were tested, under greenhouse conditions, on six newly released rice cultivars. Differences in virulence pattern were observed in pathogenic populations of 'Primavera' and 'BRS Bonança'. Isolates with virulence to improved cultivars were common in samples from farmers' fields in the absence of aloinfection. The virulence frequency of P. grisea isolates collected from 'Primavera'' to cultivars 'BRS Vencedora', 'BRS Colosso', 'BRS Liderança', 'BRS Soberana', 'BRS Curinga' and 'BRS Talento', was high in descending order. On the other hand, in the fungus population of 'BRS BRS Bonança' virulence frequency was high in 'BRS Talento', followed by 'BRS Curinga', 'BRS Vencedora', 'BRS Liderança', 'BRS Colosso' and 'BRS Soberana'. While virulence to 'BRS Talento' was rare among isolates from 'Primavera', it was most frequent in isolates of 'BRS Bonança'. The six improved rice cultivars permitted to differentiating agriculturally important virulences in the pathogen population which can be utilized in selecting breeding lines for specific resistance, in rice blast improvement program.

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No presente trabalho, o autor trata da formação de campo petrolífero que se teria formado às expensas de organismos planctónicos, misturados com areia das dunas, material esse que teria sido transportado pelo vento. Refere-se, assim, o autor, ao campo petrolífero de "Wilmington", situado na Ilha Terminal, ao sul de Los Angeles, California. Esse campo, que já fora descrito, em 1943, por GILLULY & GRANT, faz parte do Mioceno e do Plioceno inferior, achando-se separado dos schistos Jurássicos metamórficos, por uma discordância localizada a 6.000 pés de profundidade. O conjunto das camadas petrolíferas alcança espessura de 1 .500 pés, sendo cada uma delas separada das outras por estratos do "siltstone" (siltito). O tamanho dos grãos, nos dois tipos de rochas, é o de depósitos eólicos, mas, ao contrário do que acontece em depósitos sub-aéreos, esses grãos são angulosos ou sub-angulosos. De acordo com MCNAUGHTON , esses depósitos se teriam formado em profundidade crescente, de 200 a 5.000 pés; esse fato, relacionado com as dimensões dos grãos, leva a crer que o material tenha sido transportado pelo vento. A sedimentação deu-se longe da costa, de maneira muito lenta, provavelmente em consequência de tempestades de excepcional intensidade. O petróleo teria sido produzido por organismos planctónicos que se teriam misturado com areia das dunas, sendo a velocidade da sedimentação desta, muito menor. Os cálculos indicam que foram armazenados somente 23% dos hidrocarbonetos que caíram sobre a areia de sedimentação, sob a forma de organismos mortos. M. V.

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Maranhão state in Brazil presents a big potential for the cultivation of several oleaginous species, such as babassu, soybean, castor oil plant, etc... These vegetable oils can be transformed into biodiesel by the transesterification reaction in an alkaline medium, using methanol or ethanol. The biodiesel production from a blend of these alcohols is a way of adding the technical and economical advantages of methanol to the environmental advantages of ethanol. The optimized alcohol blend was observed to be a methanol/ethanol volume ratio of 80 % MeOH: 20 % EtOH. The ester content was of 98.70 %, a value higher than the target of the ANP, 96.5 % (m/m), and the biodiesel mass yield was of 95.32 %. This biodiesel fulfills the specifications of moisture, specific gravity, kinematic viscosity and percentages of free alcohols (methanol plus ethanol) and free glycerin.

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Palm oil is one of the two most important vegetable oils in the world's oil and fats market. The extraction and purification processes generate different kinds of waste generally known as palm oil mill effluent (POME). Earlier studies had indicated the possibility of using boiler fly ash to adsorb impurities and colour in POME treatment. The adsorption treatment of POME using boiler fly ash was further investigated in detail in this work with regards to the reduction of BOD, colour and TSS from palm oil mill effluent. The amount of BOD, colour and TSS adsorbed increased as the weight of the boiler fly ash used was increased. Also, the smaller particle size of 425µm adsorbed more than the 850µm size. Attempts were made to fit the experimental data with the Freundlich, Langmuir and Dubinin-Radushkevich isotherms. The R² values, which ranged from 0.8974-0.9898, 0.8848-0.9824 and 0.6235-0.9101 for Freundlich, Langmuir and Dubinin-Radushkevich isotherms respectively, showed that Freundlich isotherm gave a better fit followed by Langmuir and then Dubinin-Radushkevich isotherm. The sorption trend could be put as BOD > Colour > TSS. The apparent energy of adsorption was found to be 1.25, 0.58 and 0.97 (KJ/mol) for BOD, colour and TSS respectively, showing that sorption process occurs by physiosorption. Therefore, boiler fly ash is capable of reducing BOD, Colour and TSS from POME and hence could be used to develop a good adsorbent for POME treatment.

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Sea buckthorn (Hippophaë) berries are ingredients of the Chinese traditional medicine. In addition to China, they are nowadays cultivated for food in several European countries, Russia, Canada, the USA, and Japan. Sea buckthorn berries are a rich source of flavonoids, mainly flavonol glycosides and proanthocyanidins. Depending on the genetic background, growth conditions, and ripeness of the berries, vitamin C concentrations up to over 1 g/100 ml juice, have been reported. Sea buckthorn berries contain inositols and methyl inositols, components of messenger molecules in humans. Sea buckthorn seed oil is rich in essential aplha-linolenic and linoleic acids, whereas the most abundant fatty acids in the berry oil are palmitoleic, palmitic and oleic acids. Other potentially beneficial lipophilic compounds of sea buckthorn seeds and berries include carotenoids, phytosterols, tocopherols and tocotrienols. The effects of sea buckthorn fractions on inflammation, platelet aggregation, oxidation injuries, the liver, skin and mucosa, among others, have been reported. The aim of the thesis work was to investigate the health effects of sea buckthorn berries and oil in humans. The physiological effects of sea buckthorn berries, berry components, and oil have mostly been studied in vitro and in animal models, leaving a demand for more clinical trials. In the first randomized, placebo-controlled trial of this thesis healthy adults consumed 28 g/day of sea buckthorn berries for three months. The main objective was to investigate the effects on the common cold. In addition, effects on other infections, inflammation and circulating lipid markers associated with cardiovascular disease risk were studied. In the second randomized, placebocontrolled trial participants reporting dry eye symptoms consumed 2 g/day of sea buckthorn oil from the seeds and berries for three months. The effects on symptoms and clinical signs of dry eye were monitored. In addition, the effects on circulating markers of inflammation and liver functions were analyzed. Sea buckthorn berries did not affect the common cold or other infections in healthy adults. However, a decrease in serum C-reactive protein was detected, indicating effects on inflammation. Fasting concentrations of serum flavonols, typical to sea buckthorn berry, increased without affecting the circulating total, HDL, LDL cholesterol, or triacylglycerol concentrations. Tear film hyperosmolarity and activation of inflammation at the ocular surface are among the core mechanisms of dry eye. Combined sea buckthorn berry and seed oil attenuated the rise in tear film osmolarity taking place during the cold season. It also positively affected some of the dry eye symptoms. Based on the tear film fatty acid analysis, the effects were not mediated through direct incorporation of sea buckthorn oil fatty acids to tear film lipids. It is likely that the fatty acids, carotenoids, tocopherols and tocotrienols of sea buckthorn oil affected the inflammation of the ocular surface, lacrimal and/or meibomian glands. The effects on the differentiation of meibomian gland cells are also possible. Sea buckthorn oil did not affect the serum concentrations of inflammation markers or liver enzymes investigated. In conclusion, this thesis work suggests positive effects of sea buckthorn berries and oil on inflammation and dry eye, respectively, in humans.

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Mobiltelefonen uppfanns år 1970, den förta komerciella produkten lanserades 1983 och marknaden för mobiltelefoner tog kraftigt fart 1986. Exemplet belyser fenomenet innovation såsom ett mångårigt, ofta upptill tio år eller årtionden, vilket är forkningsansatsen i doktorsavhandlingen. Studien har betraktat fenomenet utgående från ett företagsledningsperspektiv, inte som ett innovations projekt vilket är det trditionella perspektivet. Forskningen bygger vidare på kritiken mot den allmänna uppfattningen att nystartade små och entrepreneursdrivna företag är idealomgivningen för innovation. I forskningen har studerats gamla och stora innovativa konsumentvaruföretag. De sex studerade företagen drivs inte längre av företagets grundare, hans tankar, nätverk, ledningssätt, utan är mera influerat av strukturer, system och prosesser som och iståndsatts av en annan professionell ledning. Denna ledning har i viss mån förmått att professionalisera sättet hur innovation hanteras framgångsrikt i företaget. I forskningen har den innovativa företagsledningens tankevärld och dynamiken i tänkandet definierats. Genom studien framkommer dels tre påtagliga tankemönster och dels en generell beskrivning av ledningen för ett innovativt företag. Kärnan i arbetet definierar ledningens uppmärksamhetsområde vilket är kritiskt för att det innovativa tillståndet och cykeln för innovation har fortbestått. Innovationsaktivisternas roll är avgörande, där produkten formas som en funktion av idéer som någon har och jobbar med, av beslutsfattadet i företaget, samt av tolkning och slutledningen av företagets gällande och framtida verksamhetsvilkor. Detta kritiska uppmärksamhetsområde har även testats och verifierats i avhandlingen. Ur forskningen framstår belägg och ett förslag till en teori, med vilken det är möjligt att förklarar skillnaden i ledningens tänkande vid betraktelsen av de innovativa företagen och de icke-innovativa företagen.

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Tutkimuksessa tarkastellaan suomalaisiin yliopistoihin valikoitumista 2000-luvun alussa. Tarkastelu pohjautuu yliopistoon hakeneiden, opiskelemaan hyväksyttyjen ja opiskelupaikkaa ilman jääneiden taustojen vertailuun. Tutkimuksen tarkoituksena on selvittää, miten koulutuksellinen tasa-arvo toteutuu opiskelemaan pääsyssä. Erityistä huomiota kiinnitetään sukupuolten, eri-ikäisten, sosiaalisten ryhmien sekä eri alueella asuvien opiskelijavalinnoissa pärjäämiseen. Lisäksi pohditaan, millaiset taustatekijät ovat yhteydessä opiskelemaan pääsyyn ja miten suomalainen yliopistokenttä on lohkoutunut yliopistoittain ja aloittain hakijoiden ja sisään päässeiden taustojen perusteella. Tutkimuksen pääaineistona on henkilöpohjainen rekisteriaineisto, joka on laadittu valtakunnallisen hakijarekisterin (HAREK) ja Tilastokeskuksen yhteistyönä. Aineisto käsittää 40 %:n satunnaisotoksen vuonna 2003 suomalaisiin yliopistoihin hakeneista (N = 55 790). Aineiston muuttujat kuvaavat hakijoiden taustoja, elämäntilannetta, aiempaa koulutusta ja lapsuudenperheen asemaa. Tutkimuksessa hyödynnetään lisäksi kokonaisjoukosta muodostettua taulukkoaineistoa (N = 139 668). Yliopistoihin hakevat eivät ole yhtenäinen ryhmä. Vaikka suurin osa hakijoista oli nuoria, oli joukossa myös varttuneempia hakijoita, jotka olivat ehtineet hankkia koulutusta ja muuta elämänkokemusta. Päävalinnat toimivat siten myös aikuishakijoiden hakuväylänä; erillisvalintoja eivät hyödynnä läheskään kaikki, joilla siihen olisi mahdollisuus. Klusterianalyysin avulla hakijoista voitiin erottaa neljä ryhmää: 1) nuoret ylioppilaat, 2) toisen tutkinnon suorittajat, 3) koulutuspääoman kartuttajat sekä 4) aikuiset lisäkouluttautujat. Opiskelemaan pääsyyn vaikuttavia tekijöitä analysoitiin logistisen regressioanalyysin avulla. Analyysin mukaan hakijan iällä oli muista taustatekijöistä riippumaton vaikutus opiskelemaan pääsyyn niin, että todennäköisyys päästä yliopistoon vähenee hakijan iän kohotessa. Parhaiten opiskelemaan pääsivät kaikkein nuorimmat, alle 20-vuotiaat hakijat, jotka siis useimmiten ovat saman kevään ylioppilaita. Vanhemmille hakijoille oli usein kertynyt jo koulutusta, mutta aiemmat tutkinnot paransivat sisäänpääsyn mahdollisuuksia vain, mikäli ne olivat korkea-asteelta. Alemmilla ammatillisilla tutkinnoilla oli pikemminkin opiskelemaan pääsyä heikentävä vaikutus. Myös se, mitä hakija oli tehnyt ennen valintakokeita, vaikutti sisäänpääsyn mahdollisuuksiin. Parhaiten valinnoissa pärjäsivät päätoimiset opiskelijat, heikoiten työttömät hakijat. Vaikka miesten hyväksymisprosentit olivat keskimäärin korkeammat kuin naisten, sukupuoli ei osoittautunut itsenäiseksi opiskelemaan pääsyä selittäväksi tekijäksi. Naisten huonompi pärjääminen valinnoissa selittyykin pitkälti sukupuolten eriytyneillä alavalinnoilla. Naisten suosimat alat kun ovat pääsääntöisesti vaikeapääsyisempiä kuin miesten. Tutkimuksessa selvisi myös, että kaupunkilaisuus lisäsi todennäköisyyttä tulla hyväksytyksi. Toisaalta opiskelemaan pääsy erosi myös asuinmaakunnittain, mikä kertoo lähinnä siitä, että eri yliopistojen sisäänpääsyasteissa on varsin suuria eroja. Yliopistojen lohkoutuminen hakijoiden sosiaalisen taustan mukaan oli paljon selvempää kuin alojen. Kaikki pääkaupunkiseudun yliopistot – lukuun ottamatta Teatterikorkeakoulua – luokittuivat isän asemalla mitaten elitistisiksi. Matalimmista taustoista haettiin Lapin, Joensuun ja Vaasan yliopistoihin. Alojen paikka elitistisyyskansanomaisuus -ulottuvuudella vaihteli suuresti yliopistoittain. Teknillistieteellinen, matemaattis-luonnontieteellinen ja kauppatieteellinen ala sijoittuivat kuitenkin keskimääräistä ylemmäs, kun taas kasvatustiede ja farmasia olivat kansanomaisimpia hakukohteita. Opiskelijaksi valikoitumisen peruselementit toistuivat myös tässä tutkimuksessa: koulutetuimpien ja hyvässä asemassa olevien vanhempien jälkeläiset saivat opiskelupaikan useammin kuin muut. Yliopistolaitoksessa vuosikymmenten saatossa toteutetut rakenteelliset muutokset eivät siis ole muuttaneet valikoitumisen peruslinjaa, joskin uutena huomiona nousi maanviljelijöiden jälkeläisten hyvä valinnoissa pärjääminen. Maanviljelijäperheestä tulevien opiskelemaan pääsyn todennäköisyys oli kaikkein suurin.

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There are reasons of necessity in bio-fuel use and bio-energy fast development. It includes the material about bio-energy technologies, applications and methods. There are basic thermodynamics and economic theories. The economic calculation presents the comparison between two combinations. There are boiler plant below 20 MW in combination with ablative pyrolysis plant for bio-oil production and CHP plant below 100 MW in combination with the RTP pyrolysis bio-oil production technology. It provides a material about wood chips and bio-oil characteristics and explains it nature, presents the situation around the bio-fuel market or bio-fuel trade. There is a description of pyrolysis technologies such as ablative and RTP. The liquid product of the pyrolysis processes is bio-oil. The bio-oil could be different even of the same production process, because of the raw material nature and characteristics. The calculation shows advantages and weaknesses of combinations and obtained a proof of suppositions. The next thing, proven by this work is the fact that to get more efficiency from energy project it is good possibility to built plants in combinations.

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The time required to regrowth a forest in degraded areas depends on how the forest is removed and on the type of land use following removal. Natural regeneration was studied in abandoned old fields after intensive agricultural land use in areas originally covered by Brazilian Atlantic Forests of the Anchieta Island, Brazil in order to understand how plant communities reassemble following human disturbances as well as to determine suitable strategies of forest restoration. The fields were classified into three vegetation types according to the dominant plant species in: 1) Miconia albicans (Sw.) Triana (Melastomataceae) fields, 2) Dicranopteris flexuosa (Schrader) Underw. (Gleicheniaceae) thickets, and 3) Gleichenella pectinata (Willd.) Ching. (Gleicheniaceae) thickets. Both composition and structure of natural regeneration were compared among the three dominant vegetation types by establishing randomly three plots of 1 x 3 m in five sites of the island. A gradient in composition and abundance of species in natural regeneration could be observed along vegetation types from Dicranopteris fern thickets to Miconia fields. The gradient did not accurately follow the pattern of spatial distribution of the three dominant vegetation types in the island regarding their proximity of the remnant forests. A complex association of biotic and abiotic factors seems to be affecting the seedling recruitment and establishment in the study plots. The lowest plant regeneration found in Dicranopteris and Gleichenella thickets suggests that the ferns inhibit the recruitment of woody and herbaceous species. Otherwise, we could not distinguish different patterns of tree regeneration among the three vegetation types. Our results showed that forest recovery following severe anthropogenic disturbances is not direct, predictable or even achievable on its own. Appropriated actions and methods such as fern removal, planting ground covers, and enrichment planting with tree species were suggested in order to restore the natural forest regeneration process in the abandoned old fields.

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ABSTRACT The objectives of this study were to morphologically characterize fruits of the babassu palm tree (Attalea vitrivir) and to estimate their productivity in the north of Minas Gerais State, Brazil. Twenty mature fruits were collected from 10 plants in three different areas in Januária, Minas Gerais. Eighteen biometric parameters of the fruits were measured, the oil contents of the seeds was determined, the adherence to normal distribution was evaluated, distribution frequencies were evaluated and the effects of individuals and areas on the variables and the correlations between them were analyzed. The production of fruit bunches per plant and the number of fruits per bunch from 10 plants were quantified in three areas and the potential production under both natural harvesting and cultivation conditions were estimated. Significant differences were found among all of the biometric parameters examined between the different individuals and the different areas, which shows wide morphological variability in the fruits. The average oil content was 45.7%, but with significant differences among individuals. The observed variability favors the selection of productive individuals in genetic improvement programs. The potential productivity of endocarps and oil based on a density of 400/plants per hectare would be respectively 6.4 and 1.2 tons/ha, which indicates the possibility of using A. vitrivir for producing charcoal, bio fuels, and for carbon fixation.

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ABSTRACT This study aimed to estimate the genetic correlation among selection ages (juvenile - adult) and efficiency of early selection for the height, diameter, and volume traits of individuals from Pinus taeda families propagated via somatic embryogenesis. This study was carried out by genetic-statistical analysis, estimation procedure of variance (Reml), and prediction components of breeding values (Blup), using the Selegen-Reml/Blup software. Genetic correlations among juvenile ages and rotation age were performed by applying the linear model developed by Lambeth (1980). In accordance with results of the established model, the early selection can be performed in clones of Pinus taeda with high selection efficiency. Ages from 4 to 6 years old are enough to select Pinus taeda clones propagated via somatic embryogenesis for harvesting at 8 and 12 years old; and 6 to 10 years old are enough to select them for harvesting at 20 years old. On the basis of the genetic correlations estimates from the environments, the clones' selection of Pinus taeda propagated via somatic embryogenesis should be developed specifically for each environment. The clones' selection can be performed considering the diameter due to the high correlation between volume and diameter.

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The energy balance for the production of sunflower oil and cake was carried out during the agricultural and industrial stage phase, where it was considered a cold extraction by hydraulic pressing, with the plant location in a rural area with a radius of 30km range. Data on productivity was used in two varieties of sunflower (Helio 358 and Aguará 04) grown in different seasons (2007/2008, 2008/2009), under different irrigation levels. Data showed that irrigation resulted in an increase in productivity of both varieties, and the best response was observed for Aguará 04 variety. Moreover, the increased intensity of irrigation negatively affected the energy balance, reducing the ratio between energy produced and energy used in the production chain. The most significant inputs in the energy intake were fertilizer followed by diesel oil, when irrigation was not used for. When the irrigation technique was used, the most significant inputs, in order of representativeness, were: energy, fertilizer and equipment.

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Brazil is doing a major effort to find alternatives to diesel oil as combustible. Some study lines are oriented to the development of vegetable oils used as fuel, as a source of getting cheaper and have higher energy density than the converted vegetable oils, and less risk of environmental contamination. The aim of this study was to evaluate the performance, the useful life of the lubricant and some components of a Diesel Cycle engine, with an electronic injection system, in a long-term test operating with a preheated blend (65°C) of 50% (v v-1) of soybean oil in petrodiesel. There was a reduction of the useful life of the injectors which presented failure because of high wear with 264 hours of operation and showed an increase in emissions of particulate matter (opacity) which may be assigned to the failures occurred in the injection system. An increase in the useful life of the lubricant, when compared with the literature was also observed. The electronic injection system may favor the burning of the tested fuel. The test was interrupted with 264 hours because of failures in the injection system.

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The aim of this research was to evaluate the effects of different irrigation depths and potassium dosages, of Jatropha seed oil content and yield. The experimental design used was randomized blocks, in split-plots, with four replicates. The treatments were four water depths (plots) and four potassium dosages (subplots) applied through irrigation water. The water depths were applied based on the percentage of accumulated evaporation of a Class A (ECA) tank and of rainfall, as following: L0 = without irrigation, L40, L80 and L120, representing 40, 80 and 120% of the balance, respectively. The potassium dosages were K30, K60, K90 and K120 (30, 60, 90 and 120kg ha-1 of potassium, respectively). The oil extraction of samples was done through chemical extraction by organic solvent. The seeds used in this test were from the sampling of two seed productions from 2009, second year of crop production. It was possible to observe that irrigation use increased oil yield and decreased the oil content of Jatropha seed. Potassium fertilization did not influence oil content and yield. There was a relative increase of efficiency in water use producing oil until certain water depth, and after that there was a decrease.