Littérature scientifique sur le sujet « Butanol and isobutanol »
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Articles de revues sur le sujet "Butanol and isobutanol"
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Kanno, Manabu, Taiki Katayama, Hideyuki Tamaki, Yasuo Mitani, Xian-Ying Meng, Tomoyuki Hori, Takashi Narihiro et al. « Isolation of Butanol- and Isobutanol-Tolerant Bacteria and Physiological Characterization of Their Butanol Tolerance ». Applied and Environmental Microbiology 79, no 22 (6 septembre 2013) : 6998–7005. http://dx.doi.org/10.1128/aem.02900-13.
Texte intégralRésumé :
ABSTRACTDespite their importance as a biofuel production platform, only a very limited number of butanol-tolerant bacteria have been identified thus far. Here, we extensively explored butanol- and isobutanol-tolerant bacteria from various environmental samples. A total of 16 aerobic and anaerobic bacteria that could tolerate greater than 2.0% (vol/vol) butanol and isobutanol were isolated. A 16S rRNA gene sequencing analysis revealed that the isolates were phylogenetically distributed over at least nine genera:Bacillus,Lysinibacillus,Rummeliibacillus,Brevibacillus,Coprothermobacter,Caloribacterium,Enterococcus,Hydrogenoanaerobacterium, andCellulosimicrobium, within the phylaFirmicutesandActinobacteria. Ten of the isolates were phylogenetically distinct from previously identified butanol-tolerant bacteria. Two relatively highly butanol-tolerant strains CM4A (aerobe) and GK12 (obligate anaerobe) were characterized further. Both strains changed their membrane fatty acid composition in response to butanol exposure, i.e., CM4A and GK12 exhibited increased saturated and cyclopropane fatty acids (CFAs) and long-chain fatty acids, respectively, which may serve to maintain membrane fluidity. The gene (cfa) encoding CFA synthase was cloned from strain CM4A and expressed inEscherichia coli. The recombinantE. colishowed relatively higher butanol and isobutanol tolerance thanE. coliwithout thecfagene, suggesting thatcfacan confer solvent tolerance. The exposure of strain GK12 to butanol by consecutive passages even enhanced the growth rate, indicating that yet-unknown mechanisms may also contribute to solvent tolerance. Taken together, the results demonstrate that a wide variety of butanol- and isobutanol-tolerant bacteria that can grow in 2.0% butanol exist in the environment and have various strategies to maintain structural integrity against detrimental solvents.
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Nor, Azah Ramli, et A. Rahman Roshanida. « Isobutanol Production and Alcohol Tolerance by Yeast Wild Strain ». Advanced Materials Research 1113 (juillet 2015) : 334–39. http://dx.doi.org/10.4028/www.scientific.net/amr.1113.334.
Texte intégralRésumé :
Recently, there have been global movements toward reducing the use of fossil resources as source of energy due to continuous depletion of petroleum fuel-reserves besides contributing to environmental problems such as greenhouse effect, global warming and climate change. Isobutanol is one of biomass-based fuels that has been recognizes for its potentiality as fuel additive or substitute due to its attractive physical properties. This paper investigates the production of isobutanol and alcohol tolerance by five different types of yeast (Saccharomyces cerevisiae,Kluyveromyces lactisGG799 andPichia pastorisKM71H, GS115 and X33) in batch fermentation. Based on the result obtained,P.pastorisX33 produced the highest concentration of isobutanol at 65 mg/l followed byP.pastorisGS115,K.lactisGG799,P.pastorisKM71H andS.cerevisiaewith concentration of 57 mg/l, 49 mg/l 49 mg/l and 46 mg/l respectively. This result proves that yeast is able to produce isobutanol naturally.S. cerevisiaehas been proven as good yeast in alcohol tolerance as it was capable to grow in more than 2% isobutanol and butanol of up to 2%. Among the different alcohols tested for alcohol tolerance, 3-methyl-1-butanol has the highest toxicity towards yeast growth as compared to isobutanol and butanol.
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Bravo-Sánchez, Micael G., Gustavo A. Iglesias-Silva, Alejandro Estrada-Baltazar et Kenneth R. Hall. « Densities and Viscosities of Binary Mixtures of 2-Butanol + Isobutanol, 2-Butanol + tert-Butanol, and Isobutanol + tert-Butanol from (308.15 to 343.15) K ». Journal of Chemical & ; Engineering Data 58, no 9 (16 août 2013) : 2538–44. http://dx.doi.org/10.1021/je400423u.
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Zernecke, R., T. Frank, K. Haegler, J. Albrecht, H. Bruckmann et M. Wiesmann. « Correlation analyses of detection thresholds of four different odorants ». Rhinology journal 49, no 3 (1 août 2011) : 331–36. http://dx.doi.org/10.4193/rhino10.263.
Texte intégralRésumé :
The detection threshold task of the Sniffin` Sticks can be conducted using two different odorants - n-butanol or phenylethyl alcohol (PEA). Previous studies show contradictory results regarding the correlation analysis of the two odorants. The current study investigated the relationship between PEA and n-butanol with respect to previous findings and subject population. We compared four different odorants (PEA, n-butanol, isoamyl butyrate, isobutanol) in an olfactory detection threshold task depending on subject population. Test odorants were applied to 73 healthy subjects. The experiment was divided into two sessions performed on two different days. The correlation coefficient between individual thresholds of PEA and n-butanol was not significant when exclusively normosmic subjects were included, but significant when additionally hyposmic, older subjects were studied. Comparable results were found for the analysis of the odorants n-butanol and isoamyl butyrate. Correlation between n-butanol and isobutanol was significant, both for exclusively normosmic, and additionally older, hyposmic subjects. The analyses of all other odorants revealed no significant correlations. Results give explanations for previous contradictory findings regarding investigations of PEA and n-butanol in a detection threshold task, and indicate that a formal validation of the Sniffin` Sticks with PEA as odorant is required.
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Riggio, Roque, Hector E. Martinez, Norma Z. de Salas et Juan F. Ramos. « Densities, viscosities, and refractive indexes of tert-butyl methyl ether + butyl alcohols at 298.15 K ». Canadian Journal of Chemistry 73, no 3 (1 mars 1995) : 431–34. http://dx.doi.org/10.1139/v95-056.
Texte intégralRésumé :
Densities, viscosities, and refractive indexes of three binary systems, tert-butyl methyl ether +n-butanol, +sec-butanol, +isobutanol, have been determined at 298.15 K and atmospheric pressure over the complete composition range. We also report calculated excess properties including molar volume, viscosity, and Gibbs free energy for the activation of flow for these systems. Keywords: binary systems, excess properties.
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Decoté, Paulo André Prata, Amanda Puttin Vidoto, Maristela de Araujo Vicente et Maria de Fatima Pereira dos Santos. « Reciclagem de óleo lubrificante ferroviário usado utilizando extração por solventes verdes assistido por ultrassom indireto ». Revista Ibero-Americana de Ciências Ambientais 12, no 6 (28 mai 2021) : 426–47. http://dx.doi.org/10.6008/cbpc2179-6858.2021.006.0036.
Texte intégralRésumé :
O objetivo deste estudo foi investigar a reciclagem do óleo lubrificante ferroviário por extração com solventes orgânicos polares assistida por uso indireto de ultrassom que fundamentou nos parâmetros de solubilidade de Hansen e nos critérios de sustentabilidade para a seleção de solventes orgânicos. Foi determinado o parâmetro de solubilidade de Hansen do óleo lubrificante ferroviário comercial com 25 solventes orgânicos. Os resultados da esfera de solubilidade do óleo, o parâmetro de solubilidade experimental e os dados teóricos de 1236 solventes, e o critério de sustentabilidade, foram utilizados para selecionar os melhores solventes extratores polares isobutanol, 1-butanol e metil etil cetona. feito um planejamento experimental de mistura Simplex-Lattice [3, 3] do processo de extração do óleo recuperado em banho de ultrassom de 37 kHz na temperatura de 30 °C no tempo de exposição de 5 min. A mistura solvente/óleo foi submetida a dois processos de extração: uso de ultrassom indireto (banho) e agitação mecânica, como controle. Os resultados mostraram que os parâmetros de solubilidade do óleo lubrificante ferroviário comercial foram 15,8, 3,8 e 7,6 MPa0.5 para o parâmetro de dispersão, polar e ligação de hidrogênio, respectivamente. A qualidade do óleo recuperado após o procedimento de extração, foi avaliada pela densidade, viscosidade cinemática a 40 °C até 100 °C e Índice de Viscosidade. Os rendimentos de recuperação de óleo usando US foram de 64,0% m/m (isobutanol), 89,1% m/m (1-butanol) e 91,2% m/m (MEK). Os rendimentos para agitação mecânica nas mesmas condições foram inferiores ao encontrados em US: 56,3% m/m, 83,4% m/m e 89,1% m/m para os solventes isobutanol, 1-butanol e MEK, respectivamente. Os óleos recuperados com os solventes isobutanol, 1-butanol e MEK apresentaram, respectivamente, Índice de Viscosidade de 73, 84 e 88 para US e de 68, 76 e 82 para AM. Portanto, o uso de ultrassom é promissor para auxiliar no processo de reciclagem de óleo lubrificante ferroviário usado.
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Trinh, Cong T., Johnny Li, Harvey W. Blanch et Douglas S. Clark. « Redesigning Escherichia coli Metabolism for Anaerobic Production of Isobutanol ». Applied and Environmental Microbiology 77, no 14 (3 juin 2011) : 4894–904. http://dx.doi.org/10.1128/aem.00382-11.
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ABSTRACTFermentation enables the production of reduced metabolites, such as the biofuels ethanol and butanol, from fermentable sugars. This work demonstrates a general approach for designing and constructing a production host that uses a heterologous pathway as an obligately fermentative pathway to produce reduced metabolites, specifically, the biofuel isobutanol. Elementary mode analysis was applied to design anEscherichia colistrain optimized for isobutanol production under strictly anaerobic conditions. The central metabolism ofE. coliwas decomposed into 38,219 functional, unique, and elementary modes (EMs). The model predictions revealed that during anaerobic growthE. colicannot produce isobutanol as the sole fermentative product. By deleting 7 chromosomal genes, the total 38,219 EMs were constrained to 12 EMs, 6 of which can produce high yields of isobutanol in a range from 0.29 to 0.41 g isobutanol/g glucose under anaerobic conditions. The remaining 6 EMs rely primarily on the pyruvate dehydrogenase enzyme complex (PDHC) and are typically inhibited under anaerobic conditions. The redesignedE. colistrain was constrained to employ the anaerobic isobutanol pathways through deletion of 7 chromosomal genes, addition of 2 heterologous genes, and overexpression of 5 genes. Here we present the design, construction, and characterization of an isobutanol-producingE. colistrain to illustrate the approach. The model predictions are evaluated in relation to experimental data and strategies proposed to improve anaerobic isobutanol production. We also show that the endogenous alcohol/aldehyde dehydrogenase AdhE is the key enzyme responsible for the production of isobutanol and ethanol under anaerobic conditions. The glycolytic flux can be controlled to regulate the ratio of isobutanol to ethanol production.
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Chen, Chang-Ting, et James C. Liao. « Frontiers in microbial 1-butanol and isobutanol production ». FEMS Microbiology Letters 363, no 5 (31 janvier 2016) : fnw020. http://dx.doi.org/10.1093/femsle/fnw020.
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Elfasakhany, Ashraf. « Dual and Ternary Biofuel Blends for Desalination Process : Emissions and Heat Recovered Assessment ». Energies 14, no 1 (24 décembre 2020) : 61. http://dx.doi.org/10.3390/en14010061.
Texte intégralRésumé :
Desalination using fossil fuels is so far the most common technique for freshwater production worldwide. However, such a technique faces some challenges due to limited fossil fuels, high pollutants in our globe, and its high energy demand. In this study, solutions for such challenges were proposed and investigated. Renewable biofuel blends were introduced and examined as energy/sources for desalination plants and, in turn, reduced dependency on fossil fuels, enhanced pollutants, and recovered energy for desalinations. Eight different blended biofuels in terms of dual and ternary blend approaches were investigated. Results displayed that dual and ternary blends of gasoline/n-butanol, gasoline/isobutanol, gasoline/n-butanol/isobutanol, gasoline/bioethanol/isobutanol, and gasoline/bioethanol/biomethanol were all not highly recommended as energy sources for desalination units due to their low heat recovery (they showed much lower than the gasoline, G, fuel); however, they could provide reasonable emissions. Both gasoline/bioethanol (E) and gasoline/biomethanol (M) provided high heat recovery and sensible emissions (CO and UHC). Gasoline/bio-acetone was the best one among all blends and, accordingly, it was upper recommended for both heat recovery and emissions for desalination plants. In addition, both E and M were recommended subsequently. Concerning emissions, all blends showed lower emissions than the G fuel in different levels.
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Bogataj, Miloš, Zdravko Kravanja et Andreja Nemet. « Recovery of N-Butanol from a Complex Five-Component Reactive Azeotropic Mixture ». Processes 10, no 2 (14 février 2022) : 364. http://dx.doi.org/10.3390/pr10020364.
Texte intégralRésumé :
This paper proposes a concept of a process design for the separation and recovery of n-butanol from a five-component mixture, consisting of n-butanol, isobutanol, formaldehyde, water and methanol. The mixture is a common waste stream in the production of butylated amino resins; therefore, recovery of n-butanol is crucial to the efficiency of the process. The results show that up to 94% of the n-butanol present in the waste stream can be recovered. Under the studied conditions, 99.76% pure n-butanol can be obtained, while formaldehyde, water and methanol are present only in traces. The energy intensity of the process is estimated at 2.42 MJ/kg of purified n-butanol. The economic analysis of the process shows that the process is economically viable over a wide range of production capacities, as evidenced by high net present values and high return on investment values.
Thèses sur le sujet "Butanol and isobutanol"
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Gerebring, Linnéa. « Yeast Saccharomyces cerevisiae strain isolated from lager beer shows tolerance to isobutanol ». Thesis, Linköpings universitet, Institutionen för fysik, kemi och biologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-129066.
Texte intégralRésumé :
The development of biofuels has received much attention due to the global warming and limited resources associated with fossil fuels. Butanol has been identified as a potential option due to its advantages over ethanol, for example higher energy density, compatibility with current infrastructure and its possibility to be blended with gasoline at any ratio. Yeast Saccharomyces cerevisiae can be used as a producer of butanol. However, butanol toxicity to the host limits the yield produced. In this study, four strains of yeast isolated from the habitats of lager beer, ale, wine and baker ́s yeast were grown in YPD media containing isobutanol concentrations of 1.5 %, 2 %, 3 % and 4 %. Growth was measured to determine the most tolerant strain. Gene expression for the genes RPN4, RTG1 and ILV2 was also measured, to determine its involvement in butanol stress. The genes have in previous studies seen to be involved in butanol tolerance or production, and the hypothesis was that they all should be upregulated in response to butanol exposure. It was found that the yeast strain isolated from lager beer was most tolerant to isobutanol concentrations of 2 % and 3 %. It was also found that the gene RPN4 was upregulated in response to isobutanol stress. There was no upregulation of RTG1 or ILV2, which was unexpected. The yeast strain isolated from lager beer and the gene RPN4 is proposed to be investigated further, to be able to engineer a suitable producer of the biofuel butanol.
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Heinrup, Rebecka. « Evaluation of isobutanol tolerance and gene expression in four different Saccharomyces cerevisiae strains for the development of bio-butanol production ». Thesis, Linköpings universitet, Biologi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-132314.
Texte intégralRésumé :
Today, most transportation fuels are derived from crude oil. However, fossil fuels are limited resources and contribute to climate change, and are therefore not considered as sustainable. Biofuels are highly relevant candidates for replacing fossil fuels and research has gone into butanol as a biofuel. It has a high energy density, is less hygroscopic and can be blended up to 85% with gasoline. The yeast Saccharomyces cerevisiae is considered a good host for bio- butanol production; it produces small amounts of isobutanol naturally through the Ehrlich pathway, is easy to manipulate genetically and can therefore be engineered to produce higher titres of butanol. End-product toxicity, however, is a problem that needs to be solved to make butanol production in S. cerevisiae more effective, since the organism cannot tolerate higher concentrations of butanol than 2%. Four different S. cerevisiae strains were cultivated in 1.5%, 2%, 3% and 4% isobutanol by spot tests and in liquid media to evaluate their tolerance. Gene expression was measured for genes RPN4, RTG1 and ILV2 to examine their up-regulation and relevance in butanol tolerance. S. cerevisiae strain Saflager 34/70 was determined as the most tolerant strain and was able to grow in 2% liquid isobutanol and 3% isobutanol on agar plates. A three-fold up-regulation of RPN4, a transcription factor involved in the regulation of proteasome gene expression, was observed. These results contribute to the progress of genetic engineering of butanol host organisms, which is needed to create a more effective production of butanol as a biofuel.
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LONGO, VALERIA. « A protein-based biorefinery for bulk chemicals production ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2013. http://hdl.handle.net/10281/41977.
Texte intégralRésumé :
A biorefinery should ideally integrate biomass conversion processes to
produce a range of fuels, power, materials, and chemicals from biomass.
The term biorefinery is derived both from the raw material feedstock
which is renewable biomass and also from the bioconversion processes
often applied in the treatment and processing of the raw materials.
Renewable sources are the basis of the alternative energy, fuels and
compound obtained in a biorefinery-based way to meet the energy
demand in a world where petrol fuels are becoming scarce and more
expensive.
The current biorefinery schemes are mainly based on hexose sugars (first
generation) or lignocellulosic-based material (second generation) as
feedstocks and depend on microbial cell factories for obtaining the
products of interest. In most cases, the substrate utilization is not
optimized jet: at the end of the process in addition to the main product,
by-products such as huge quantity of lignin and some C5 sugars (deriving
from incomplete utilization of lignocellulose) but also proteins (mainly
the exhausted biomass at the end of the production) are still available.
Focusing the attention on proteins, they are nowadays mainly absorbed as
animal feed, but the quantities produced exceed the demand. Considering
the implication related to GMO utilization and the increasing number of
biorefineries, it can be stated that proteins could represent an interesting
Abstract
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“no-cost” starting material to produce more biofuel, bioproducts or
biopower in a biorefinery-based way.
This study has the aim to present some examples of production by using
the protein side-stream of a biorefinery. In particular, we report the
possible destiny of two aminoacids released from said proteins: glycine,
to obtain butanol and isobutanol, and glutamate, to produce succinic acid.
Butanol represents the most feasible alternative to gasoline, but,
differently from ethanol, microbial fermentations are not enough
developed to sustain the market demand. The natural producers, different
species of the Gram positive group of Clostridia, present many and
different limitations which are challenging the scientific communities in
finding alternative hosts.
Among the different alternative hosts, yeasts can present attractive
features, being the most relevant the existence of industrial plants based
on Saccharomyces cerevisiae fermentation for the production of ethanol.
Up to now, in S. cerevisiae the production of butanol has been obtained
by expressing heterologous genes from Clostridia. The best reported
butanol titer is only 2.5 mg/L, probably mainly depending on problems
related to the overexpression of heterologous prokaryotic enzymes. On
the contrary, the isobutanol production is obtained at high level (0.63 g/L)
in S. cerevisiae by using and optimizing an endogenous valine
degradation pathway.
We present an alternative and novel way to produce butanol and
isobutanol using glycine as substrate, through a new identified and
Abstract
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biochemically characterized pathway. Starting from 15 g/L of glycine we
have obtained 92 mg/L of butanol and 58 mg/L of isobutanol.
Considering that the pathway has been just discovered and no
optimization has been designed or applied, the obtained results has to be
considered extremely positive.
Since one of the most common stresses that microorganisms have to face
during productions is the toxicity of the final product, we investigated
also the possibility to use the glycine as protective agent for the cells.
This idea originated from different studies that explain how the use of
aminoacids, among which glycine, can help the cells to better respond to
different stresses, such as high ethanol concentration and hydrogen
peroxide. As never reported in literature, we have notably found that
butanol causes a sort of oxidative stress, peroxidising the membrane
lipids. Moreover, we have demonstrated that glycine can help the cells to
better tolerate the presence of hydrogen peroxide, acetic acid, ethanol and
butanol.
The succinic acid occurs naturally in humans, animals, plants, and
microorganisms as TCA cycle intermediate. Its use as a precursor to
produce many important commodity chemicals used to make a wide
assortment of products such as solvents, fiber and polymer production
make it one of the most important relevant bulk chemicals. The microbial
production of succinic acid via reductive TCA cycle using engineered
Saccharomyces cerevisiae is nowadays on the market commercialised by
Reverdia (Cassano Spinola, Italy).
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Here we investigated the possibility to exploiting the glutamate
degradation pathway through the γ-aminobutyric acid (GABA)
intermediate as an additional way of obtaining succinate when a source of
glutamate is feeded to the cells. Since this pathway, also called
GAD/GABA shunt, is transcriptionally controlled, we transcriptionally
up-regulated it through the constitutive overexpression of the involved
genes, GAD1, UGA1 and UGA2. Even if the pathway was clearly
overexpressed, as revealed by transcriptional analysis, the obtained
amount of succinic acid did not reflect this modification. Further
investigating the possible reason of that, we have demonstrated that,
despite the higher transcription levels, the corresponding enzymatic
activities of the pathway did not increased. We can argue that posttranslational
regulations occur in the pathway, what at the moment
impaired the initial aim of our work. However, the data add new and
relevant information for the comprehension of the role and the regulation
of this pathway in S. cerevisiae. It cannot be excluded that the production
of succinic acid in yeasts might be in a future optimized by exploiting the
GAD/GABA pathway, once it will be fully characterized.
We have finally investigated the possibility to produce succinic acid in a
strain of S. cerevisiae deleted in the gene encoding the enzyme glutamate
synthase, GLT1. During this study we have tested different growing
conditions, since the target gene of deletion is located in a critical node of
the nitrogen sensing and utilization, which is related to cellular plasticity
and adaptability in perturbed environment. We could demonstrate that
Abstract
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when cells are growing in low salts concentration medium, the deleted
strain compared to wild type strain is able to accumulate more reduced
products, such as succinic acid, malate/fumarate, glycerol and ethanol,
indicating a sort of necessity to reduce the excess of NAD(P)H generated
by the GLT1 deletion. Regarding this preliminary study, deeper
investigations have to be performed to find a fine tuned way to
intentionally redirect the metabolic flux and obtain the product of interest,
which in turn could be succinic acid, but also malic or fumaric acid, or
again ethanol, being this last the product that has the responsibility to
prove that bio-based second generation processes can effectively and
positively have an impact on our future society.
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BERTERAME, NADIA MARIA. « Exploitation of Saccharomyces cerevisiae for the challenging conversion of renewable substrates into biofuels and chemicals ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2015. http://hdl.handle.net/10281/67452.
Texte intégralRésumé :
Le risorse fossili sono a oggi la principale fonte sfruttata dall’uomo per la produzione di energia elettrica e combustibili, nonché come materia prima per l’industria, in particolare quella chimica. Il progressivo esaurimento dei giacimenti, che a sua volta determina un innalzamento dei prezzi, insieme alla necessità di una maggior sostenibilità ambientale hanno contribuito ad aumentare l’interesse verso fonti alternative.
All’interno di tale contesto si pone il presente lavoro, volto alla produzione sia di un composto chimico di rilevante importanza, l’acido lattico, che di due biocarburanti promettenti, il butanolo e l’isobutanolo, utilizzando Saccharomyces cerevisiae come cell factory e materia organica derivante da biomasse come substrati.
S. cerevisiae è un microrganismo promettente per la produzione industriale di acido lattico poiché è in grado di crescere a pH inferiori rispetto ai batteri lattici, naturali produttori. Ciò permette di evitare almeno in parte l’uso di basi e dunque di diminuire i costi associati al recupero del prodotto che deve essere in forma acida. Tuttavia, il maggior limite per la produzione di acidi organici è rappresentato dall’effetto tossico delle alte concentrazioni di prodotto raggiunte durante il processo; per tali ragioni in questo lavoro è stata valutata sia la tolleranza di ceppi di laboratorio di S. cerevisiae all’acido lattico sia la sua produzione.
In particolare, è stata valutata la modulazione dell’espressione del gene SAM2, codificante l’enzima S-adenosilmetionina sintetasi responsabile della sintesi dell’S-adenosilmetionina, cofattore centrale del metabolismo cellulare. La delezione di tale gene ha determinato sia un incremento della tolleranza all’acido, nel ceppo di laboratorio BY4741, che un incremento di circa il 5% della sua produzione (~69 g/L) nel ceppo industriale omolattico-fermentante m850. Inoltre, sono stati valutati gli effetti dell’esposizione all’acido lattico sulle principali classi di biomolecole di S. cerevisiae. In presenza dell’acido, sono stati osservati aggregati proteici ed effetti sulla composizione lipidica della membrana. Poiché il gene OPI1 è coinvolto nel pathway biosintetico della fosfatidilcolina, principale fosfolipide di membrana, è stato valutato l’effetto della sua delezione. Ciò ha determinato una maggior tolleranza all’acido lattico nel ceppo BY4741.
Gli alcoli superiori possiedono delle proprietà chimico-fisiche che li rendono competitivi rispetto alla benzina e possono essere utilizzati direttamente come biocarburanti nei motori e distribuiti attraverso le infrastrutture esistenti.
Nel presente lavoro ci si è focalizzati sulla produzione di butanolo e isobutanolo in ceppi di laboratorio di S. cerevisiae. Nello specifico, l’attenzione è stata volta al pathway dei chetoacidi, derivanti dagli amminoacidi. Tale via metabolica è promettente in quanto permette di sfruttare le proteine che si accumulano nel corso degli attuali processi produttivi di biocarburanti e biomateriali.
Villas-Boas ha proposto un modello in cui a partire dall’amminoacido glicina, passando dal gliossilato, può generarsi il cheto-acido α-chetovalerato che a sua volta può essere convertito in α-isochetovalerato. Poiché in letteratura inoltre è riportata la conversione dell’α-chetovalerato in butanolo e dell’α-isochetovalerato in isobutanolo, nel presente lavoro è stato ipotizzato e dimostrato step by step il pathway di produzione di tali alcoli a partire da glicina in due diversi background genetici di S. cerevisiae. In particolare, a partire da 15 g/L di glicina sono stati ottenuti 92 mg/L di butanolo e 58 mg/L di isobutanolo.Fossil resources are the main source exploited by human society for the production of electricity and fuels, as well as raw materials for the production of fine and bulk chemicals. The gradual depletion of deposits, which in turn causes an increase in prices, along with the increasing demand and need for environmental sustainability have contributed to trigger the interest in alternative energy and chemical sources. Within this context, the present work aimed at the production of one relevant chemical, lactic acid, and two promising biofuels, butanol and isobutanol, exploiting Saccharomyces cerevisiae as cell factory and organic material derived from biomass as substrates. S. cerevisiae is a promising alternative microorganism for lactic acid production since it can grow at a lower pH than the lactic acid bacteria, the natural producers. This allows to partly avoid the use of bases and thus decreasing the costs associated with the recovery of the product, which must be in the acid form. Despite the high robustness of yeasts, the major limitation for a viable production of organic acids is the toxic effect of the very high concentrations of product reached during the process; therefore, in this work the tolerance of laboratory strains of S. cerevisiae to lactic acid and its production have been evaluated. In particular, the modulation of the expression of SAM2 has been studied. This gene encodes for the enzyme S-adenosylmethionine synthetase, responsible for the synthesis of S-adenosylmethionine, central cofactor of cellular metabolism. The deletion of SAM2 resulted in an increase in lactic acid tolerance, in the BY4741 genetic background, and in an increase of its production (~ 69 g/L, approximately 5% more than in the parental strain) in the industrial omolactic strain m850. Furthermore the effects of lactic acid exposure on the main biomolecule classes of S. cerevisiae were investigated. Remarkably, under stressful condition, protein aggregates and changes in membrane lipid composition were observed. Since OPI1 is involved in the biosynthetic pathway of phosphatidylcholine, the main membrane phospholipid, the effect of its deletion was evaluated. Remarkably, OPI1 deletion resulted in an increased lactic acid tolerance in the laboratory strain BY4741. Higher alcohols are considered as promising gasoline substitutes because of their high energy density and the possibility of their use in currently engine as well as storage and distribution using existing infrastructure. The aim of this study was the production of two higher alcohols, butanol and isobutanol, in laboratory strains of S. cerevisiae. Specifically, the attention was focused on the pathway of keto-acids that branches out from amino acid pathway. The keto-acid pathway appears to be promising since it might exploit as substrate the proteins accumulated during industrial production processes starting from lignocellulosic biomass pre-treatment. Villas-Boas (2005) proposed a metabolic model in which glycine, through glyoxylate, can be converted into α-ketovalerate which in turn can be converted into α-isoketovalerate. It is known from literature that the conversion of α-ketovalerate can generate butanol as well as the conversion of α-isoketovalerate generates isobutanol. Therefore, in the present work a novel pathway for the production of butanol and isobutanol from glycine was hypothesized and demonstrated in two different S. cerevisiae genetic background. In particular, starting from 15 g/L of glycine 92 mg/L of butanol and 58 mg/L of isobutanol have been obtained.
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Lima, Iara Batista de. « Medidas do primeiro coeficiente Townsend de ionização em gases inibidores de descargas ». Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-18062014-132035/.
Texte intégralRésumé :
No presente trabalho são apresentados resultados referentes ao primeiro coeficiente Townsend de ionização (α) no isobutano puro, para a faixa de campo elétrico reduzido (E/N) de 145 até194 Td. A configuração do aparato experimental consiste de uma configuração semelhante a uma RPC, com o anodo constituído por um vidro de elevada resistividade (2 x 1012 Ωcm) e um catodo metálico, ligado diretamente a um eletrômetro, onde fotoelétrons são produzidos pela incidência de um feixe de laser pulsado. O coeficiente α é determinado por meio da medição da corrente elétrica em regime de ionização primária e em regime de avalanche. Uma vez que, para o isobutano puro não há valores experimentais disponíveis na literatura, para a faixa de E/N analisada por este trabalho, os valores obtidos foram comparados com os resultados da simulação Magboltz 2. Os estudos incluíram a determinação do coeficiente α para diferentes taxas de repetição e intensidades do feixe de laser. Como a relação entre a carga rápida e a total relaciona-se com o primeiro coeficiente de Townsend, estudos relativos à contribuição iônica e eletrônica para a corrente média também foram realizados. Como existem poucos resultados disponíveis na literatura referentes às secções de choque de colisão e parâmetros de transporte para o isobutano é comum considerar os resultados de seu isômero estrutural: o n-butano. Assim, a fim de realizar uma análise comparativa, o coeficiente α foi determinado também para o n-butano.In the present work, results concerning the first Townsend ionization coefficient (α) in pure isobutane within the density-normalized electric field (E/N) range of 145 to 194 Td are presented. The experimental setup consists of RPC-like cell with the anode made of a high resistivity glass (2 x 1012 Ωcm) and a metallic cathode, directly connected to an electrometer, on which photoelectrons are produced by the incidence of a pulsed laser beam. The α coefficient is determined by measuring the current under primary ionization and avalanche regime. Since for the E/N range covered by this work, there are no experimental values for pure isobutane available in the literature, the obtained values were compared with Magboltz 2 results. Our studies included the determination of α coefficient for different repetition rates and laser beam intensity. The ratio of the fast charge to the total charge is related to the first Townsend coefficient, so studies concerning the ionic and the electronic contribution to the average current were also performed. Since there are few results available in the literature for isobutane, concerning collisional cross section and electron transport parameters, is common to consider results from its structural isomer: n-butane. Thus, in order to perform a comparative analysis, the coefficient α was also determined for n-butane.
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Vivaldini, Túlio Cearamicoli. « Medidas de velocidade de arrastamento de elétrons em gases inibidores de descargas pelo método de Townsend pulsado ». Universidade de São Paulo, 2014. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-10072014-155715/.
Texte intégralRésumé :
O deslocamento de elétrons em gases pode ser caracterizado por grandezas macroscópicas tais como a velocidade de arrastamento, taxa de ionização, primeiro coeficiente de Townsend e os coeficientes de difusão longitudinal e transversal, que são denominados de parâmetros de transporte. Esses parâmetros são importantes já que permitem a validação das secções de choque de colisões de elétrons com as moléculas do gás, contribuem com informações para modelos de descargas automantidas e são importantes para o desenvolvimento de novos detectores gasosos. Neste trabalho são apresentados os resultados de velocidade de arrastamento (W), taxa de ionização (Ri) e do primeiro coeficiente Townsend de ionização (α), para o isobutano e n-butano em função do campo elétrico reduzido efetivo no intervalo de 130 a 180 Td, obtidos utilizando a técnica de Townsend pulsada. Em nosso aparato, os elétrons primários são gerados a partir da incidência no catodo de um curto pulso de laser e são acelerados em direção ao anodo por meio de um campo elétrico uniforme. O sinal elétrico proveniente do deslocamento desses elétrons é digitalizado por um osciloscópio e a partir do ajuste de uma função modelo à forma do sinal elétrico, determinam-se os parâmetros de transporte. Os resultados obtidos para o isobutano e n-butano foram comparados com os valores da simulação Magboltz 2-versão 8.6 em razão da escassez de dados na literatura para esses gases na região de campo elétrico reduzido estudada.The electron swarm can be characterized by macroscopic quantities such as the drift velocity, ionization rate, first Townsend ionization coefficient and the longitudinal and transverse diffusion coefficients, so called transport parameters. These parameters are important since they allow the validation of electron collisional cross section with gas molecules, contribute for self-sustained discharge models and are important for gaseous detectors development. In the present work the results of electron drift velocity (W), ionization rate (Ri) and first Townsend coefficient (α) as a function of the reduced electric field for isobutane and n-butane by the means of pulsed Townsend technique are presented. In our experimental setup, the primary electrons are liberated by the irradiation of a short laser pulse at the cathode and are accelerated towards the anode through a uniform electric field. The electron movements induce signals that are digitalized and the fitting of a model function to their waveforms provides the transport parameters. The results obtained for isobutane and n-butane were compared with Magboltz 2-version 8.6 values, since there are few data in the literature for these gases for effective reduced electric field ranging from 130 to 180 Td.
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Cuylan, Gokhan. « Development Of Property Equations For Butane And Isobutane ». Master's thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12610670/index.pdf.
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This study aims to simulate a vapor compression refrigeration cycle, working with either butane (R-600) or isobutane (R-600a). For this purpose a computer program is written to design a household refrigerator, by modeling a steady-state, vapor compression cycle, with user defined input data. Each refrigerator component can be designed separately, as well as parts of a single refrigeration system in the program.
In order to determine the refrigerant thermophysical properties at different states, least squares polynomial equations for different properties of R-600 and R-600a have been developed.
Computer program is used for refrigeration cycle analysis, variable speed compressor design and calculating coefficient of performance (COP) and irreversibility of the cycle.
Sample-preliminary designs have been carried out for different refrigeration loads, room and cold space temperatures with the program, to compare the performance characteristics of the refrigerants. Designs have been performed at different refrigeration loads, room and cold space temperatures. It is observed that for the same conditions R-600 has slightly better performance characteristics than those of R-600a.
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Petri, Anna Raquel. « Medidas do primeiro coeficiente de Townsend de ionização em misturas gasosas utilizadas em microdosimetria ». Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-05052017-152207/.
Texte intégralRésumé :
Microdosímetros gasosos geralmente empregam uma mistura gasosa equivalente ao tecido humano mole (Tissue-equivalent Gas TEG), composta de um hidrocarboneto, dióxido de carbono e nitrogênio, de forma que o poder de freamento na mistura e no tecido sejam semelhantes. Entretanto, independentemente do hidrocarboneto adotado, dados tanto teóricos como experimentais do primeiro coeficiente de Townsend de ionização (α) nestas misturas são raros, ainda que a primeira TEG, cujo metano é o gás majoritário, tenha sido proposta em 1956 por Rossi e Failla e continue sendo amplamente utilizada. Neste trabalho, dados do parâmetro α em TEGs baseadas no metano (CH4 64,4%, CO2 32,4% e N2 3,2%) e nos isômeros do butano (C4H10 51,4%, CO2 42,3% e N2 6,3%) são apresentados pela primeira vez em geometria planar para a faixa de campo elétrico normalizado pela densidade do gás (E/N) entre 100 290 Td (1 Td = 10-21 V.m2). O método de medidas adotado baseia-se na técnica de Townsend pulsada, onde o primeiro coeficiente de Townsend pode ser determinando comparando a corrente elétrica no regime de avalanche e a corrente de ionização primária gerada pela incidência de um feixe de laser de nitrogênio em um eletrodo metálico (catodo) de uma câmara de geometria planar, sendo o anodo um eletrodo de alta resistividade (ρ=2×1010Ω.m). O aparato experimental, até então operado apenas em pressão atmosférica, foi modificado para também trabalhar em baixa pressão (120 hPa), de modo a aumentar a faixa de E/N investigada. A validação do método e das alterações do sistema de detecção foi realizada utilizando os três gases componentes das TEGs cujos parâmetros de transporte são amplamente estudados: o nitrogênio, o dióxido de carbono e o metano. Observou-se que o parâmetro na TEG com metano assemelha-se com os valores determinados para o metano puro. Na TEG baseada no isobutano, ele é compatível com o primeiro coeficiente de Townsend do dióxido de carbono para campos acima de 170 Td. Já o parâmetro na mistura com n-butano é intermediário entre os valores obtidos para o dióxido de carbono e o nitrogênio. Os resultados experimentais, disponíveis em forma tabular, foram comparados com os simulados utilizando o programa Magboltz 2, evidenciando boa concordância dentro da incerteza experimental.Gaseous microdosimeters usually employ a Tissue-equivalent Gas (TEG), made of a hydrocarbon, carbon dioxide and nitrogen, in order to make similar the stopping power in this mixture and in the human soft tissue. Notwithstanding, regardless the chosen hydrocarbon, both theoretical and experimental data on the first Townsend ionization coefficient (α) in this mixtures are rare, even though the first TEG, which methane is the most abundant gas, was proposed in 1956 by Rossi and Failla and it has been widely employed since then. In this work, data on the parameter α in TEGs based on methane (CH4 64.4%, CO2 32.4%, and N2 3.2%) and butanes isomers (C4H10 51.4%, CO2 42.3% e N2 6.3%) are presented for the first time in planar geometry in the gas density-normalized electric field (E/N) range between 100 290 Td (1 Td = 10-21 V.m2). The adopted method is based on the Pulsed Townsend Technique, where the first Townsend coefficient can be determined by comparing the electric current in the avalanche mode and the primary ionization current, produced by an nitrogen laser beam incidence in a metallic electrode (cathode) of a parallel plate chamber, which the anode is a resistive electrode (ρ=2×1010Ω.m). The experimental setup, previously operated only at atmospheric pressure, was adapted to work also at low pressure (120 hPa), in order to increase the investigated E/N range. The validation of both method and detection system modifications was made by employing three TEGs components, nitrogen, carbon dioxide and methane, whose transport parameters are extensively studied. The parameter in the methane-based TEG follows the behavior observed in pure methane. In the isobutane-based TEG, it is compatible with the first Townsend coefficient in carbon dioxide for E/N above 170 Td. The parameter in the n-butane-based TEG lies between the obtained values of in carbon dioxide and nitrogen. The experimental results, included in tabular form, agree with those from Magboltz 2 simulations within the experimental uncertainties.
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Glos, Stefan. « Präzisions-Dichtemessungen von Propan, Propylen, n-Butan und Isobutan sowie Entwicklung eines Normdichtemessgerätes für die Erdgasindustrie ». [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=972452583.
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Shen, Wei. « Alkylation of isobutane/1-butene over acid functionalized mesoporous materials ». Thesis, Université Laval, 2010. http://www.theses.ulaval.ca/2010/27073/27073.pdf.
Texte intégralLivres sur le sujet "Butanol and isobutanol"
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Organisation, International Labour, International Program on Chemical Safety., United Nations Environment Programme, World Health Organization et WHO Task Group on Environmental Health Criteria for Butanols (1985 : Geneva, Switzerland), dir. Butanols, four isomers : 1-butanol, 2-butanol, tert-butanol, isobutanol. Geneva : World Health Organization, 1987.
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Organisation, International Labour, United Nations Environment Programme et World Health Organization, dir. Isobutanol health and safety guide. Geneva : World Health Organization, 1987.
Trouver le texte intégralChapitres de livres sur le sujet "Butanol and isobutanol"
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Zhang, Xianping, Xiaowei Fan, Xinli Wei, Fang Wang et Xiaojing Zhang. « Research on Condensation Pressure and Temperature of Heat Pumps Using Blends of CO2 with Butane and Isobutane ». Dans Lecture Notes in Electrical Engineering, 791–97. Berlin, Heidelberg : Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-39581-9_78.
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« Butane, Isobutane, and Propane ». Dans Medical Toxicology of Drug Abuse, 684–90. Hoboken, NJ, USA : John Wiley & Sons, Inc., 2012. http://dx.doi.org/10.1002/9781118105955.ch42.
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Domingo, M. Aviado, Samir Zakhari et Tetsuya Watanabe. « Hydrocarbon Mixture : Propane, Butane, And Isobutane ». Dans Non-fluorinated Propellants and Solvents for Aerosols, sous la direction de Leon Golberg, 75–80. CRC Press, 2018. http://dx.doi.org/10.1201/9781351075015-7.
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Fan, Li, Takashi Watanabe et Kaoru Fujimoto. « Supercritical-phase oxidation of isobutane to t-butanol by air ». Dans Natural Gas Conversion V, Proceedings ofthe 5th International Natural Gas Conversion Symposium,, 581–86. Elsevier, 1998. http://dx.doi.org/10.1016/s0167-2991(98)80494-1.
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PITZER, KENNETH S. « Thermodynamics of Gaseous Hydrocarbons : Ethane, Ethylene, Propane, Propylene, n-Butane, Isobutane , 1-Butene, Cis and Trans 2-Butenes, Isobutene, and Neopentane (Tetramethylmethane) ». Dans World Scientific Series in 20th Century Chemistry, 15–21. WORLD SCIENTIFIC, 1993. http://dx.doi.org/10.1142/9789812795960_0005.
Texte intégralActes de conférences sur le sujet "Butanol and isobutanol"
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TOLENTINO, MARISTELA, ADRIANO PINTO MARIANO et Guilherme Pereira. « Avaliação energética e ambiental de usinas para produção de biocombustíveis (etanol / n-butanol / isobutanol) ». Dans XXIV Congresso de Iniciação Científica da UNICAMP - 2016. Campinas - SP, Brazil : Galoa, 2016. http://dx.doi.org/10.19146/pibic-2016-52071.
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Kumar, Naveen, Sidharth Bansal et Vipul Vibhanshu. « Potential Utilization of Higher Alcohols in Unmodified Diesel Engine ». Dans ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-64618.
Texte intégralRésumé :
India does not have large reserves of crude petroleum and spends a huge amount of foreign exchange for importing crude petroleum. The environmental degradation caused by burning of petroleum derived fuels is also causing an ecological imbalance. Research is carried world over on renewable fuels which could either be used as an extender or substitute to petroleum origin fuels and in this context alcohols such as ethanol and butanol have an immense potential. The earlier work on use of alcohols as a blend with diesel in the compression ignition engine has suggested reduction in emissions, however, problems such as phase separation and increase in fuel consumption has also been encountered while utilizing ethanol in diesel engines. To alleviate this problem, isobutanol has the potential to be used along with ethanol to make a homogenous blend without any phase separation and simultaneous advantage of alcohol being an oxygenated fuel which shall improve the combustion and reduce emission. The present study was carried out to explore the potential utilization of ethanol-isobutanol-diesel blends (containing up to 20% ethanol-isobutanol mixture in equal proportions) in compression ignition engine. Three blends were prepared having 5%, 10%, 20% ethanol-isobutanol mixtures respectively and calorific value, kinematic viscosity; specific gravity and density of blends were found to decrease with increase in ethanol-isobutanol percentage. The engine trial was conducted on an unmodified diesel engine to evaluate the performance and emission characteristics on ethanol-isobutanol-diesel blends and results were compared with baseline data of diesel. The results obtained from the engine trial suggested that brake thermal efficiency (BTE) increased and brake specific energy consumption (BSEC) decreased for the blends and considerable reduction in carbon monoxide (CO) and carbon dioxide (CO2) was observed with blends with a small increase in unburnt hydrocarbon (UBHC). The nitrogen oxide (NOx) and smoke emissions were also found to reduce for the ethanol-isobutanol-diesel blends.
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Bounefour, Oumayma, et Ahmed Ouadha. « Thermodynamic Analysis and Working Fluid Optimization of a Combined ORC-VCC System Using Waste Heat From a Marine Diesel Engine ». Dans ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-39976.
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This paper examines through a thermodynamic analysis the feasibility of using waste heat from marine Diesel engines to drive a vapor compression refrigeration system. Several working fluids including propane, butane, isobutane and propylene are considered. Results showed that isobutane and Butane yield the highest performance, whereas propane and propylene yield negligible improvement compared to R134a for operating conditions considered.
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Wilk, R. D., R. M. Green, W. J. Pitz, C. K. Westbrook, S. Addagarla, D. L. Miller et N. P. Cernansky. « An Experimental and Kinetic Modeling Study of the Combustion of n-Butane and Isobutane in an Internal Combustion Engine ». Dans International Congress & Exposition. 400 Commonwealth Drive, Warrendale, PA, United States : SAE International, 1990. http://dx.doi.org/10.4271/900028.
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Moloney, Francesca, Eydhah Almatrafi, D. Y. Goswami et Elias Stefanakos. « Working Fluid Analysis for Supercritical Organic Rankine Cycles for Medium Geothermal Reservoir Temperatures ». Dans ASME 2017 Power Conference Joint With ICOPE-17 collocated with the ASME 2017 11th International Conference on Energy Sustainability, the ASME 2017 15th International Conference on Fuel Cell Science, Engineering and Technology, and the ASME 2017 Nuclear Forum. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/power-icope2017-3618.
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A steady state model of a supercritical organic Rankine cycle (SORC) was created in MATLAB and validated. Fluid properties were obtained using NIST REFPROP. Various working fluids were tested, including pentane (R601), isopentane (R601a), butane (R600), isobutane (R600a), butene, and cis-butene. Pentane and isopentane have not been of focus for SORCS at these temperatures. Varying turbine inlet temperatures ranging from 170 to 240°C were tested with the heat source provided by a medium temperature geothermal reservoir. A parametric analysis was performed on varying inlet pressure and turbine inlet temperature in comparison to first law efficiency, second law efficiency, effectiveness, and net work produced to analyze the overall and exergetic performance of each fluid. Optimum first law efficiency ranged from 17 to 22%. Cis-butene and pentane performed the best in all performance factors analyzed. Pentane and isopentane performed the best at pressures near or below their critical point. It was also found that near the critical temperature, a subcritical ORC has better performance than an SORC. This study is beneficial for not only geothermal energy but for applications that can provide operating temperatures between 170 to 240°C.
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Kanoğlu, Mehmet, et Yunus A. Çengel. « Improving the Performance of an Existing Air-Cooled Binary Geothermal Power Plant : A Case Study ». Dans ASME 1998 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/imece1998-0839.
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Abstract An existing air-cooled binary geothermal power plant in Northern Nevada with an average net power output of 27 MW is studied. The current performance of the plant is analyzed with an emphasis on the effects of seasonal climate changes. Two potential sites have been identified to improve the performance of the plant. Northern Nevada has a dry climate particularly in hot summer months, and the temperature of cooling air can be decreased considerably by evaporative cooling. When the air temperature is decreased to the wet-bulb temperature, the decrease in the condenser temperature is determined to increase the power output by up to 29%. The required amount of water for this case is calculated to be about 200,000 tons per year. Several parametric studies are performed by simulating the operation of the plant with an equation solver with built-in thermophysical property functions. It is determined that the net power output of the plant can be increased by 2.8 percent by optimizing the maximum pressure in the cycle. Also, replacing the existing working fluid isobutane by other commonly used binary fluids such as butane, R-114, isopentane, and pentane can increase the net power output by up to 2.5 percent.
Rapports d'organisations sur le sujet "Butanol and isobutanol"
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Lee, Ivan C., Jeffrey G. St. Clair et Adam S. Gamson. Catalytic Oxidative Dehydration of Butanol Isomers : 1-Butanol, 2-Butanol, and Isobutanol. Fort Belvoir, VA : Defense Technical Information Center, septembre 2011. http://dx.doi.org/10.21236/ada550017.
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