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Auswahl der wissenschaftlichen Literatur zum Thema „Bio-Based fatty acids“
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Zeitschriftenartikel zum Thema "Bio-Based fatty acids"
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Stavila, Erythrina, Frita Yuliati, Azis Adharis, Joddy Arya Laksmono und Muhammad Iqbal. „Recent advances in synthesis of polymers based on palm oil and its fatty acids“. RSC Advances 13, Nr. 22 (2023): 14747–75. http://dx.doi.org/10.1039/d3ra01913f.
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Frihart, Charles R. „Chemistry of Dimer Acid Production from Fatty Acids and the Structure–Property Relationships of Polyamides Made from These Dimer Acids“. Polymers 15, Nr. 16 (09.08.2023): 3345. http://dx.doi.org/10.3390/polym15163345.
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While there is abundant literature on using a wide range of biomaterials to make polymers for various adhesive applications, most researchers have generally overlooked developing new adhesives from commercially available bio-based dimerized fatty acids. Some of the literature on the chemistry taking place during the clay-catalyzed dimerization of unsaturated fatty acids is generally misleading in that the mechanisms are not consistent with the structures of these dimers and a by-product isostearic acid. A selective acid-catalyzed interlayer model is much more logical than the widely accepted model of clay-catalyzed Diels–Alder reactions. The resulting dimers have a variety of linkages limiting large crystal formation either as oligomeric amides or polyamides. These highly aliphatic fatty acid dimers are used to make a wide range of hot melt polyamide adhesives. The specific structures and amounts of the diacids and diamines and their relative ratios have a big effect on the bio-based polyamide mechanical properties, but analysis of the structure–property relationships has seldom been attempted, since the data are mainly in the patent literature. The diacids derived from plant oils are valuable for making polyamides because of their very high bio-based content and highly tunable properties.
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Mensah, Joel B., Adrian H. Hergesell, Sebastian Brosch, Christiane Golchert, Jens Artz und Regina Palkovits. „Catalytic deoxygenation of bio-based 3-hydroxydecanoic acid to secondary alcohols and alkanes“. Green Chemistry 22, Nr. 11 (2020): 3522–31. http://dx.doi.org/10.1039/d0gc00691b.
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McDowall, Stewart Charles, Maria Braune und Roy Nitzsche. „Recovery of bio-based medium-chain fatty acids with membrane filtration“. Separation and Purification Technology 286 (April 2022): 120430. http://dx.doi.org/10.1016/j.seppur.2021.120430.
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Beller, Harry R., Taek Soon Lee und Leonard Katz. „Natural products as biofuels and bio-based chemicals: fatty acids and isoprenoids“. Natural Product Reports 32, Nr. 10 (2015): 1508–26. http://dx.doi.org/10.1039/c5np00068h.
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Narra, Naganna, Badari Narayana Prasad Rachapudi, Sahithya Phani Babu Vemulapalli und Padmaja V. Korlipara. „Lewis-acid catalyzed synthesis and characterization of novel castor fatty acid-based cyclic carbonates“. RSC Advances 6, Nr. 31 (2016): 25703–12. http://dx.doi.org/10.1039/c6ra00880a.
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Simar-Mentières, S., F. Nesslany, M. L. Sola, S. Mortier, J. M. Raimbault, F. Gondelle, L. Chabot, P. Pandard, D. Wils und A. Chentouf. „Toxicology and Biodegradability of a Phthalate-Free and Bio-Based Novel Plasticizer“. Journal of Toxicology 2021 (12.07.2021): 1–15. http://dx.doi.org/10.1155/2021/9970896.
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Phthalate esters, mainly di-ethylhexylphthalate (DEHP), represent a class of chemicals primarily used as plasticizers for polyvinyl chloride in a wide range of domestic and industrial applications. These phthalate esters are low-toxicity environmental contaminants. To address these drawbacks, POLYSORB® ID 37, a blend of diesters obtained from esterification of isosorbide with plant-based fatty acids, was developed. The company can now offer PVC manufacturers a new product which competes with phthalates and other such chemicals. The market for plasticizers is very important, and ROQUETTE intends to provide a more sustainable and safer product. Isosorbide diester is bio-based (made from glucose and vegetable fatty acids). This plasticizer is registered in REACH regulation for high volumes (>1000 T/year). Risk assessment was obtained by conducting a wide range of biodegradability and toxicological protocols, using rodent models, according to established guidelines. Overall, all of the toxicological and biodegradability studies demonstrated that POLYSORB® ID 37 is nontoxic to mammalian life and is readily biodegradable.
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Lamarzelle, Océane, Geoffrey Hibert, Sébastien Lecommandoux, Etienne Grau und Henri Cramail. „A thioglycerol route to bio-based bis-cyclic carbonates: poly(hydroxyurethane) preparation and post-functionalization“. Polymer Chemistry 8, Nr. 22 (2017): 3438–47. http://dx.doi.org/10.1039/c7py00556c.
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He, Songbo, Thomas Sjouke Kramer, Dian Sukmayanda Santosa, Andre Heeres und Hero Jan Heeres. „Catalytic conversion of glycerol and co-feeds (fatty acids, alcohols, and alkanes) to bio-based aromatics: remarkable and unprecedented synergetic effects on catalyst performance“. Green Chemistry 24, Nr. 2 (2022): 941–49. http://dx.doi.org/10.1039/d1gc03531b.
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Synergetic effects between glycerol and various co-feeds (including alkanes, alcohols, and free fatty acids) lead to higher catalytic activity, prolonged catalyst life-time, and improved catalyst regenerability for bio-based aromatics formation.
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Kulomaa, Tuomas, Jorma Matikainen, Pirkko Karhunen, Mikko Heikkilä, Juha Fiskari und Ilkka Kilpeläinen. „Cellulose fatty acid esters as sustainable film materials – effect of side chain structure on barrier and mechanical properties“. RSC Advances 5, Nr. 98 (2015): 80702–8. http://dx.doi.org/10.1039/c5ra12671a.
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Bio-based films were prepared by acylation of cellulose with saturated, unsaturated and branched fatty acids. The products showed increased thermal stability, low water vapour transmission rates and enhanced tensile and elastic properties.
Dissertationen zum Thema "Bio-Based fatty acids"
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Torella, Joseph Peter. „Synthetic biology approaches to bio-based chemical production“. Thesis, Harvard University, 2014. http://nrs.harvard.edu/urn-3:HUL.InstRepos:13088835.
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Inexpensive petroleum is the cornerstone of the modern global economy despite its huge environmental costs and its nature as a non-renewable resource. While ninety percent of petroleum is ultimately used as fuel and can in principle be replaced by sources of renewable electricity, ten percent is used as a feedstock to produce societally important chemicals that cannot currently be made at a reasonable cost through alternative processes. In this dissertation, I will discuss my efforts, together with several colleagues, to apply synthetic biology approaches to the challenge of producing renewable petrochemical replacements. In Chapter 2, I discuss our efforts to engineer E. coli to produce fatty acids with a wide range of chain lengths at high yield, thereby providing an alternative platform for the production of diverse petrochemicals. In Chapter 3, I describe a novel method of DNA assembly that we developed to facilitate synthetic biology efforts such as those in Chapter 2. This method is capable of simultaneously assembling multiple DNA pieces with substantial sequence homology, a common challenge in synthetic biology. In Chapter 4, I discuss the development of a "bionic leaf": a hybrid microbial-inorganic catalyst that marries the advantages of photovoltaic-based light capture and microbial carbon fixation to achieve solar biomass yields greater than those observed in terrestrial plants. This technology offers a potentially low-cost alternative to photosynthesis as a source of biomass and derived chemicals and fuels. The work described in this dissertation demonstrates the capacity of synthetic biology to address the problem of renewable chemical production, and offers proof of principle demonstrations that both the scope and efficiency of biological chemical production may be improved.
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Jin, Yuqin. „Biotechnological improvements of bio-based fuels and lubricants characterization of genes for branched chain fatty acids and mono-acyl esters /“. [Ames, Iowa : Iowa State University], 2007.
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Lorenzen, Jan [Verfasser], Thomas [Akademischer Betreuer] Brück, Thomas [Gutachter] Brück, Thomas [Gutachter] Fässler, Uwe [Gutachter] Bornscheuer und Wolfgang [Gutachter] Eisenreich. „Enzymatic functionalization of bio based fatty acids and algae based triglycerides / Jan Lorenzen ; Gutachter: Thomas Brück, Thomas Fässler, Uwe Bornscheuer, Wolfgang Eisenreich ; Betreuer: Thomas Brück“. München : Universitätsbibliothek der TU München, 2019. http://d-nb.info/1201819997/34.
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Claudino, Mauro. „Thiol−ene Coupling of Renewable Monomers : at the forefront of bio-based polymeric materials“. Licentiate thesis, KTH, Ytbehandlingsteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-40267.
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Plant derived oils bear intrinsic double-bond functionality that can be utilized directly for the thiol–ene reaction. Although terminal unsaturations are far more reactive than internal ones, studies on the reversible addition of thiyl radicals to 1,2-disubstituted alkenes show that this is an important reaction. To investigate the thiol–ene coupling reaction involving these enes, stoichiometric mixtures of a trifunctional propionate thiol with monounsaturated fatty acid methyl esters (methyl oleate or methyl elaidate) supplemented with 2.0 wt.% Irgacure 184 were subjected to 365-nm UV-irradiation and the chemical changes monitored. Continuous (RT– FTIR) and discontinuous (NMR and FT–Raman) techniques were used to follow the progress of the reaction and reveal details of the products formed. Experimental results supported by numerical kinetic simulations of the system confirm the reaction mechanism showing a very fast cis/trans-isomerization of the alkene monomers (<1.0 min) when compared to the total disappearance of double-bonds, indicating that the rate-limiting step controlling the overall reaction is the hydrogen transfer from the thiol involved in the formation of final product. The loss of total unsaturations equals thiol consumption throughout the entire reaction; although product formation is strongly favoured directly from the trans-ene. This indicates that initial cis/trans-isomer structures affect the kinetics. High thiol–ene conversions could be easily obtained at reasonable rates without major influence of side-reactions demonstrating the suitability of this reaction for network forming purposes from 1,2-disubstituted alkenes. To further illustrate the validity of this concept in the formation of cross-linked thiol–ene films a series of globalide/caprolactone based copolyesters differing in degree of unsaturations along the backbone were photopolymerized in the melt with the same trithiol giving amorphous elastomeric materials with different thermal and viscoelastic properties. High thiol–ene conversions (>80%) were easily attained for all cases at reasonable reaction rates, while maintaining the cure behaviour and independent of functionality. Parallel chain-growth ene homopolymerization was considered negligible when compared with the main coupling route. However, the comonomer feed ratio had impact on the thermoset properties with high ene-density copolymers giving networks with higher glass transition temperature values (Tg) and a narrower distribution of cross-links than films with lower ene composition. The thiol–ene systems evaluated in this study serve as model example for the sustainable use of naturally-occurring 1,2-disubstituted alkenes at making semi-synthetic polymeric materials in high conversions with a range of properties in an environment-friendly way.Vegetabiliska oljor som innehåller dubbelbindningar kan användas direkt för thiolene reaktioner. Trots att terminala dubbelbindningar är mycket mer reaktiva än interna visar dessa studier att den reversibla additionen av thiyl radikaler till 1,2-disubstituerade alkener är en viktig reaktion. För att undersöka tiol–ene reaktionerna, som ivolverar dessa alkener förbereddes stökiometriska blandningar av en trifunktionell propionat tiol och enkelomättade fettsyrametylestrar (metyloleat eller metyl elaidat) samt 2.0 vikt.% Irgacure 184. Dessa blandningar utsattes för 365-nm UV strålning och de kemiska förändringarna studerades. De kemiska förändringarna analyserades med olika kemiska analysmetoder; realtid RT–FTIR, NMR och FT–Raman. Dessa användes för att analysera de kemiska reaktionerna i realtid och följa bildandet av produkterna. Reaktionsmekanismen bekräftades med hjälp av experimentella data och beräkningar av numeriska och kinetiska simuleringar för systemet. Resultaten visar en mycket snabb cis/trans-isomerisering av alkenmonomeren (<1.0 min) jämfört med den totala förbrukningen av dubbelbindningarna, vilket indikerar att det hastighetsbegränsande steget kontrolleras av väteförflyttningen från tiolen till slutprodukten. Förbrukningen av den totala omättade kolkedjan är lika med tiolförbrukningen under hela reaktionen, även om bildandet av produkten gynnas från trans-enen. Detta indikerar att den första cis/trans-isomerstrukturen påverkar kinetiken. Höga tiol-ene utbyten kan enkelt erhållas relativt snabbt utan inverkan av sidoreaktioner. Detta innebär att denna reaktion kan användas som nätverksbildande reaktion för flerfunktionella 1,2-disubstituted alkenmonomerer. Vidare användes fotopolymerisation i smälta på en serie globalid/kaprolaktonbaserade sampolyestrar med varierad grad av omättnad med samma tritiol vilket resulterade i bildandet av amorfa elastomeriska material med olika termiska och viskoelastiska egenskaper. Hög omsättning (>80%) uppnåddes relativt enkelt för samtliga blandningar oberoende av den initiala funktionaliteten. Homopolymerisation av alkenen var försumbar i jämförelse med den tiol–en-reaktionen. Mängden alkengrupper har inverkan på härdplastsegenskaperna där en hög andel alken ger en nätstruktur med högre glastransitionstemperatur (Tg). Tiol–ene reaktionen utvärderades i modellsystem baserade på naturlig förekommande 1,2-disubstituterade alkener för att demonstrera konceptet med tiol-förnätade halvsyntetiska material.
QC 20110915
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Zhao, Huiping. „I. Total synthesis of [plus or minus] ovalicin and its analogues II. Bio-based polymers from vegetable oilIII. New synthetic methods of diacetylene fatty acids“. Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/735.
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Zhao, Huiping. „I. Total synthesis of [plus or minus] ovalicin and its analogues II. Bio-based polymers from vegetable oil III. New synthetic methods of diacetylene fatty acids“. Diss., Kansas State University, 2008. http://hdl.handle.net/2097/735.
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Doctor of PhilosophyDepartment of Chemistry
Duy H. Hua
I. Ovalicin is a natural product isolated from the culture of fungus Pseudorotium ovalis Stolk, it selectively inhibit type 2 methionine amino-peptidase (MetAP 2), which related to many physiological activities such as angiogenesis. Total synthesis of [plus or minus] ovalicin, its C4(S*), C4(S*)C5(S*) stereo-isomers, and C5 regio-isomer were synthesized via an intramolecular Heck reaction of (Z)-3-(t-butyldimethyl silyloxy)-1-iodo-1,6-heptadiene utilizing a catalytic amount of palladium acetate. Subsequent epoxidation, dihydroxylation, methylation (or stereochemistry inversion before or after methylation) and oxidation led to a variety of ketones, key intermediates for synthesis of ovalicin and its analogues. Introduction of side-chain to ketones by lithium (Z)-6-methylhepta-2,5-dien-2-ide and following functional group transformation led to ovalicin and its analogues. Anti-trypanosomal activities of various ovalicin analogues and synthetic intermediates were evaluated. II. Bio-based polymers from vegetable oils are renewable and environment-friendly materials. Dihydroxylated, trihydroxylate, tetrahydroxylated and hexahydroxylated triglycerides, triamino and triisopropylamino glycerides were synthesized from model triglyceride glyceryl trioleoate. These monomers were cross-linked with 1, 4-phenylene diisocynate to make polyurethanes and polyureas. The physical properties of these polymers were examined by gel content and swelling value measurements, thermodynamic and viscoelastic properties were studied from TGA, DSC and DMA measurements. The structure-property relationship was discussed based on these measurements. III. Diacetylenic fatty acids were widely applied in material science to regulate alignment on surface and stabilize self-assembled nanomaterials. A novel synthetic method of diacetylenic fatty acids from vegetable oils was developed. Its self-assembling properties on alumina surface were measured and discussed.
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Fortier, Lucas. „Réactivité de la fonction acide carboxylique en catalyse photoredox : applications à la valorisation d'acides gras biosourcés“. Electronic Thesis or Diss., Université de Lille (2022-....), 2024. http://www.theses.fr/2024ULILR068.
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Cette thèse s'inscrit dans la recherche de procédés plus écologiques en chimie, répondant aux enjeux environnementaux actuels. Elle explore l'utilisation de molécules biosourcées et de synthèses écoresponsables, en mettant l'accent sur la photocatalyse, une approche en pleine expansion. Le travail se concentre sur le potentiel des acides carboxyliques en catalyse photoredox pour la synthèse de composés organiques d'intérêt, offrant des alternatives aux méthodes classiques souvent énergivores et peu respectueuses de l'environnement. La thèse s'articule autour de trois chapitres. Le premier présente une introduction théorique à la photocatalyse, abordant ses principes et les avancées récentes. Le deuxième chapitre développe deux nouvelles méthodes de couplage C-C décarboxylatif entre acides gras et accepteurs de radicaux, visant à produire des monomères pour des polymères biosourcés et des tensioactifs. Ce procédé exploite les acides gras biosourcés en remplacement de précurseurs pétroliers, suivant les principes de la chimie verte et visant une production durable de molécules fonctionnelles. Le troisième chapitre explore la synthèse de phtalides, composés aux propriétés biologiques et pharmacologiques importantes, via des conditions douces de photocatalyse. Cette approche évite des méthodes plus énergivores et s'appuie sur des catalyseurs organiques pour optimiser l'efficacité et la sélectivité des réactions. Ces travaux représentent une avancée dans la chimie organique et des matériaux, avec des applications pour la production de polymères biosourcés et de nouveaux produits chimiques. Ils ouvrent également des perspectives d'amélioration, notamment en explorant l'utilisation de la lumière infrarouge pour activer des réactions sous conditions encore plus doucesThis thesis contributes to the development of more environmentally friendly chemical processes, addressing current environmental challenges. It explores the use of bio-based molecules and eco-responsible syntheses, focusing on photocatalysis, rapidly expanding approaches. The research centers on the potential of carboxylic acids in photoredox catalysis for synthesizing valuable organic compounds, offering alternatives to conventional methods that are often energy-intensive and less environmentally friendly. The thesis is structured into three main chapters. The first provides a theoretical introduction to photocatalysis, covering its principles and recent advances. The second chapter develops two novel decarboxylative C-C coupling methods between fatty acids and radical acceptors, aimed at producing monomers for biobased polymers and surfactants. This process leverages bio-based fatty acids as an alternative to petroleum-derived precursors, adhering to green chemistry principles and aiming for sustainable production of functional molecules. The third chapter explores the synthesis of phthalides, compounds with significant biological and pharmacological properties, using mild photocatalytic conditions. This approach avoids more energy-intensive methods and relies on organic catalysts to optimize reaction efficiency and selectivity. This work represents an advancement in organic and materials chemistry, with applications for bio-based polymer production and the creation of new chemicals. It also opens avenues for further improvement, particularly by exploring the use of infrared light to activate reactions under even milder conditions
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Maisonneuve, Lise. „Vegetable oils as a platform for the design of sustainable and non-isocyanate thermoplastic polyurethanes“. Thesis, Bordeaux 1, 2013. http://www.theses.fr/2013BOR15218/document.
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Cette thèse porte sur la synthèse de polyuréthanes thermoplastiques plus durables à partir de dérivés des huiles végétales. La première voie étudiée est basée sur la réaction, largement utilisée, entre un diol et un diisocyanate. Aussi, pour s’affranchir de l’utilisation des diisocyanates toxiques, une approche via la polyaddition entre un bis carbonate cyclique et une diamine a également été étudiée. Pour ce faire des précurseurs bi-fonctionnels : diols, bis carbonates cycliques à 5 et 6 chainons et diamines ont été préparés à partir de dérivés de l’huile de tournesol (oléate de méthyle) et de l’huile de ricin (undécénoate de méthyle et acide sébacique). Les propriétés thermo-mécaniques des polyuréthanes et poly(hydroxyuréthane)s thermoplastiques obtenus ont pu être ajustées par le choix adapté de la structure chimique des précurseurs (gras) utilisés. Les travaux réalisés démontrent un effet de la taille du cycle du carbonate sur la réactivité. En effet, les (bis) carbonates cycliques à 6 chainons se sont avérés plus réactifs que leurs homologues à 5 chainons. De plus, la synthèse de diamines via un intermédiaire dinitrile semble très prometteuse pour le « design » d’une plateforme de diamines issues d’acides gras et de poly(hydroxyuréthane)s entièrement bio-sourcésThis thesis aims to synthesize more sustainable thermoplastic polyurethanes from vegetable oil derivatives. The first route that has been investigated is based on the well-known reaction between a diol and a diisocyanate. Then to avoid the use of diisocyanates, the route via the polyaddition of a bis cyclic carbonate and a diamine have been studied as well. For this purpose, bifunctional precursors such as diols, bis 5- and 6-membered cyclic carbonates and diamines have been prepared from sunflower oil derivative (methyl oleate) and castor oil derivatives (methyl undecenoate and sebacic acid) The thermo-mechanical properties of the PUs have been modulated by designing and selecting the chemical structure of the (fatty acid-based) monomers. The performed model reaction kinetics revealed the higher reactivity of the 6-membered cyclic carbonates compare to the 5-membered ones. Finally, the developed route to fatty acid-based diamines via dinitriles synthesis in mild conditions was really efficient and this route is really promising to develop a fatty acid based-diamines platform and fully bio-based poly(hydroxyurethane)s
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Chemin, Maud. „Valorisation des xylanes du bois : vers la synthèse de copolymères amphiphiles bio-sourcés“. Thesis, Bordeaux, 2014. http://www.theses.fr/2014BORD0302/document.
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La thèse présentée propose une nouvelle voie de valorisation des xylanes du bois par l’élaboration de nouveaux polymères bio-sourcés et amphiphiles.Après une caractérisation complète de xylanes issus du bois de hêtre, l’hydrolyse acide en milieu dilué a été optimisée afin d’obtenir des xylo-oligosaccharides d’environ 6 unités xylose par chaîne avec une seule unité acide méthylglucuronique positionnée à l’extrémité non réductrice de la chaîne. En parallèle, l’étude de l’oxydation au periodate de sodium de ces xylanes a été effectuée pour permettre l’introduction d’un nombre contrôlé de fonctions aldéhyde le long de la chaîne. La fonction aldéhyde de l’extrémité réductrice des oligomères de xylane a ensuite été fonctionnalisée par un groupement allyle ou azoture pour permettre leur couplage à des dérivés d’acide gras par ‘chimie click’.Les oligomères amphiphiles ainsi obtenus ont ensuite été étudiés pour leurs propriétés tensioactives et d’auto-assemblage. Ils présentent de bonnes propriétés de mouillage, comparables à celles du Tween®80. Les objets issus de l’auto-assemblage de ces oligomères amphiphiles ont été analysés par DLS et TEM. Ils s’auto-assemblent aussi bien dans le chloroforme que dans l’eau. Les objets formés sont sphériques et de taille micellaire (d ≤ 50 nm). Ces objets ont tendance à s’associer pour former des agrégats, surtout dans le chloroforme. Ces agrégats sont régis par des interactions assez faibles pour être éliminés par dilution. Ils peuvent également être éliminés par simple filtration.Finalement, ce travail de thèse aura abouti à la synthèse de composés amphiphiles totalement bio-sourcés, à partir de xylanes, coproduits potentiels de l’industrie papetière. Grâce à leurs propriétés tensioactives, les applications envisageables pour ces tensioactifs ‘verts’ sont nombreuses. De plus, leur caractère biocompatible et leur auto-assemblage en solution aqueuse en font de bons candidats pour l’encapsulation et la vectorisation de principes actifsThis thesis work aims to add value to xylans by designing new bio-based amphiphilic polymers.Beechwood xylans were first fully characterized before their acidic hydrolysis. The hydrolysis conditions were optimized in order to obtain well-defined xylooligosaccharides, oligomeric chains of about six xylose units that have only one methylglucuronic acid unit positioned at the non-reductive chain end. Periodate oxidation of xylans was also studied in order to form new aldehyde groups within the xylan backbone in a controlled manner. The xylooligomers were then functionalized from their reductive end with an azide or an allyl group, providing the ability to couple these oligomers to fatty acid derivatives using ‘click chemistry’.The obtained amphiphilic oligomers were finally studied according to their surfactant and self-assembly properties. Their wetting properties were found to be very good, comparable to those found with Tween®80. Moreover, they self-assembled in both chloroform and water, where their structures were characterized via DLS and TEM. The resulting particles formed had a spherical micellar morphology, with a d ≤ 50 nm. However, it was found that the particles had a tendency to form large aggregates, particularly in chloroform. The aggregates could be easily removed, either by filtration or by dilution of the sample, as the forces that govern the aggregation are low enough to allow dissociation with increasing solvent volume.As previously mentioned, this thesis work led to the synthesis of bio-based amphiphilic oligomers starting from xylans, which are a potential byproduct in the paper/pulp industry. Thanks to their surfactant properties, numerous applications can be found for such a ‘green’ surfactant. Their biocompatibility added with their self-assembly nature in aqueous media makes them an attractive molecule for active substance delivery applications
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Pereira, Beatriz D’Avó. „Development of bio-based nanoemulsions to improve physical and chemical stability of omega-3 fatty acids“. Master's thesis, 2017. http://hdl.handle.net/1822/55570.
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Dissertação de mestrado em Bioquímica Aplicada (área de especialização em Biotecnologia)Nowadays there is a high interest by the food industry to develop nutritional food products. This concept promoted the development of bio-based structures to encapsulate bioactive compounds and thus enhance their physical and chemical stability from storage up until consumption. Omega-3 (ω-3) is known for its functional properties such as improving cardiovascular health, decrease inflammation, increase cognitive function. However, ω-3 fatty acids are highly susceptible to oxidation, have intense odour and low water solubility, which makes its direct application in foods extremely difficult. In order to reduce these problems, nanoencapsulation, through nanoemulsions can be used. With this in mind, lactoferrin (Lf), a protein derived from milk with a wide range of reported biological activities (e.g. antioxidant, antimicrobial, cancer prevention) was used as natural emulsifier for the development of oil-in-water nanoemulsions for ω-3 encapsulation. The nanoemulsions were characterized and assessed by physical and chemical stability during storage. Nanoemulsions were also dried by freeze-drying and nanospray-drying and further characterized. ω-3 nanoemulsions were successfully produced through high pressure homogenization, with results showing that the concentration of Lf influenced size and superficial charge of the nanoemulsions droplets obtained. Nanoemulsions revealed physical stability when stored at 4 ºC for 69 days, while presenting instability at room temperature. The antioxidant capacity of the nanoemulsions did not show significative alterations over storage while a significative increase in oxidation was registered. Only the nanoemulsions dried by nanopray-drying presented defined structures. The rehydration of the powders resulted from freeze-drying was possible while powders obtained by nanospray-drying were not able to be rehydrated. Overall the results suggest that ω-3 nanoemulsions with physical stability can be produced using Lf while chemical stability was not achieved. The Lf nanoemulsions can also be dried to obtain powders with defined submicron particles but its rehydration its limited. This work provides important information that can be useful for the design of nanoemulsions and dry capsules aiming the encapsulation of lipophilic compounds for pharmaceutical and food applications.
Hoje em dia existe um grande interesse da industria alimentar no desenvolvimento de produtos alimentares com elevado valor nutricional. Este conceito tem promovido o desenvolvimento de estruturas de origem natural para encapsular compostos bio-ativos, permitindo melhorar a sua estabilidade química e física, desde o armazenamento até ao seu consumo. O ómega-3 (ω-3) apresenta importantes propriedades funcionais tais como a melhoria de saúde cardiovascular, diminuição de inflamação, aumento de funções cognitivas. No entanto, é extremamente suscetível a oxidação, tem um odor intenso e uma baixa solubilidade em água, o que faz com que a sua aplicação direta em alimentos seja extremamente difícil. A nanoencapsulação deste composto surge como uma alternativa para solucionar tais problemas. A Lactoferrina (Lf) uma proteína derivada do leite, com inúmeras propriedades biológicas (p.e. antioxidante, antimicrobiana, prevenção de cancro) foi usada como emulsionante natural na produção de nanoemulsões óleo-em-água para a encapsulação de ω-3, as quais foram posteriormente caracterizadas e avaliadas a nível da estabilidade física e química durante o armazenamento. Estas foram ainda submetidas a 2 diferentes processos de secagem (liofilização e nanaopray-drying). Produziram-se com sucesso nanoemulsões através de homogeneização de alta pressão, tendo-se verificado que a concentração de Lf influencia o seu tamanho e carga superficial. As nanoemulsões, revelaram estabilidade física quando armazenadas (69 dias) a 4 ºC, mas não quando armazenadas à temperatura ambiente. A capacidade antioxidante, quando armazenadas (4 ºC durante 35 dias), não apresentou alterações significativas, enquanto que os valores de oxidação aumentaram. Apenas as nanoemulsões submetidas ao processo de nanaopray-drying apresentaram uma estrutura resultante bem definida, e apenas as nanoemulsões submetidas ao processo de liofilização foram possíveis de ser rehidratadas. A presente tese permitiu verificar que nanoemulsões de ω-3, com estabilidade física, podem ser produzidas, usando Lf, no entanto não foi possível obter estabilidade química. A sua secagem permite a obtenção de estruturas definidas. Este trabalho permitiu obter informação relevante para o desenvolvimento de nanoemulsões que tenham como objetivo a encapsulação de compostos lipofílicos para aplicações alimentares e farmacêuticas.
Buchteile zum Thema "Bio-Based fatty acids"
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Ngo, Helen, Karen Wagner, Alberto Nuñez, Jianwei Zhang, Xuetong Fan und Robert A. Moreau. „New Classes of Antimicrobials: Poly-Phenolic Branched-Chain Fatty Acids“. In Natural and Bio-Based Antimicrobials for Food Applications, 209–21. Washington, DC: American Chemical Society, 2018. http://dx.doi.org/10.1021/bk-2018-1287.ch011.
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Wiedemann, Sophie C. C., Pieter C. A. Bruijnincx und Bert M. Weckhuysen. „Isostearic Acid: A Unique Fatty Acid with Great Potential“. In Chemicals and Fuels from Bio-Based Building Blocks, 51–78. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2016. http://dx.doi.org/10.1002/9783527698202.ch3.
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Shafi, Wani Khalid, M. S. Charoo und M. Hanief. „Effect of Fatty Acid Composition on the Lubricating Properties of Bio-Based Green Lubricants“. In Tribology and Sustainability, 231–50. Boca Raton: CRC Press, 2021. http://dx.doi.org/10.1201/9781003092162-16.
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Bie, Xiaomei. „Fengycin Production and Its Applications in Plant Growth and Postharvest Quality“. In Bio-Based Antimicrobial Agents to Improve Agricultural and Food Safety, 71–119. BENTHAM SCIENCE PUBLISHERS, 2024. http://dx.doi.org/10.2174/9789815256239124010006.
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Fengycin is a cyclic lipopeptide produced mainly by the Bacillus genus, which is structurally composed of a β-hydroxy fatty acid and 10 amino acids. The biosynthesis of fengycin is catalyzed by large non-ribosomal peptide synthetases. Fengycin is an amphiphilic molecule with strong surface activity and displays strong antimicrobial activity. In this chapter, the molecular structure and biological properties of fengycin, and the function and catalyzing mechanism of fengycin multienzyme were summarized. Multiple antimicrobial mechanisms of fengycin and the strategies for increasing the production of fengycin were introduced. Fengycin has the advantages of low toxicity, biodegradation and high stability. Its applications, including biological control of plant pathogens, bioremediation of a contaminated environment, postharvest disease control of fruit and vegetables, food processing and preservation, etc., were reviewed finally.
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Webster, Dean C. „Bio-based Polymers and Resins in Paints and Coatings“. In Bioplastics and Biocomposites, 249–73. Royal Society of Chemistry, 2023. http://dx.doi.org/10.1039/bk9781788010085-00249.
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Paints and coatings have been used for millennia for decoration and protection of materials. Prior to the advent of the petrochemical industry, binders for paints and coatings were of necessity based on naturally occurring materials such as shellac, oriental lacquers, and vegetable oils. As petrochemicals became available, resins based on vegetable oils such as varnishes and alkyd resins were introduced. Cellulosic materials could also be made that served well as coating materials. While petrochemical resin systems were introduced and quickly grew to supplant many of the bio-based resin systems, today, due to rising interest in sustainability, there is renewed interest in making use of bio-based materials in new types of resin chemistries. Vegetable oils and fatty acids are being transformed into new types of resin structures to yield systems having properties useful for today’s demanding applications. There is also significant activity in deriving new polymer building blocks from lignocellulose biomass having chemical structures, and therefore properties, that cannot be obtained from petrochemicals.
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Onat, B. „Applications of SPME for the Determination of Amino Acids and Peptides in Biological Matrices“. In Evolution of Solid Phase Microextraction Technology, 441–50. The Royal Society of Chemistry, 2023. http://dx.doi.org/10.1039/bk9781839167300-00441.
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In the last two decades, solid phase microextraction (SPME) has been proven to be superior to other sample preparation techniques in terms of sampling unstable metabolites in a non-invasive way through combining sampling and extraction in one step. The non-invasive equilibrium-based extraction of metabolites by SPME allows SPME tools to sample short-lived metabolites, making the discovery of intermediate metabolic compounds and sample preparation for analysis in accurate amounts possible. Among all biological compounds sampled through SPME, amino acids and short peptides have attracted significant attention recently, as they play vital roles in human metabolism, such as in the pathways of cellular signalling, neurotransmission, protein synthesis, and fatty acid metabolism. This chapter summarizes the current techniques in amino acid and peptide sample preparation through SPME. Initially, amino acid derivatization and subsequent GC-MS analysis are described. It continues with a demonstration of non-derivatization based amino acid sample preparation techniques and the extraction of small peptides from complex biological matrices through Bio-SPME.
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Assunção, Joana, Helena M. Amaro, F. Xavier Malcata und A. Catarina z. Guedes. „Extraction of Microalgal Bioactive Compounds Towards Functional Ingredients: A Biorefinery Approach with Prospects And Challenges“. In Algal Functional Foods and Nutraceuticals: Benefits, Opportunities, and Challenges, 131–83. BENTHAM SCIENCE PUBLISHERS, 2022. http://dx.doi.org/10.2174/9789815051872122010011.
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Algal bioactive compounds, including pigments, polyunsaturated fatty acids, vitamins, proteins and phenolic compounds, have a wide range of increasing applications in the pharmaceutical, nutraceutical, feed, food, and cosmetics sectors. Extraction of such compounds with the purpose of obtaining nutraceutical and food ingredients at large has been under scrutiny over the last years towards greener and more sustainable bio-based processes. The step of the extraction is indeed considered the most expensive in algal-based industrial bioprocess, mainly owing to the high processing costs and environmental impacts. Therefore, the application of a biorefinery strategy (for biomass reutilization, via choice of specific green and generally recognized as safe solvent), will certainly help attain a more feasible and competitive solution. Furthermore, emerging extraction technologies are potentially suitable for application at a large scale, as part of a multi-integrated extraction strategy. This chapter accordingly addresses the most important (micro)algal-compounds possessing bioactivities, and already or likely to be used as functional ingredients; in addition, extraction procedures thereof are discussed, bearing in mind a biorefinery strategy – with major prospects and associated challenges.
Konferenzberichte zum Thema "Bio-Based fatty acids"
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Ramasamy, Jothibasu, und Mohammad K. Arfaj. „Sustainable and Eco-Friendly Drilling Fluid Additives Development“. In International Petroleum Technology Conference. IPTC, 2022. http://dx.doi.org/10.2523/iptc-22455-ms.
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Abstract Drilling fluid is an inseparable component of drilling oil and gas wells and circulated from the day of spudding to the day of completing a well. Drilling fluid consists of a variety of chemicals to provide various properties to drilling fluid such as viscosity, fluid loss control, emulsion stability, lubricity, etc. Developing chemicals that are eco-friendly and sustainable to provide the above-mentioned properties to drilling fluid is a significant step forward taken towards sustainability and reducing carbon footprint besides suitability for aquifers and offshore environments. Several fatty acid-based products play a crucial role in drilling fluids additives development as fatty acids offer eco-friendly and bio-degradable properties. Triglycerides present in vegetable oil is a potential source of fatty acids and their derivatives. Used cooking oil (UCO) provides a perpetual and sustainable source of raw material for various types of eco-friendly additives development. Used cooking oil is subjected to simple chemical modification of base hydrolysis process and mixture of fatty acids have been obtained after completing a sequence of clean-up process of reaction mixture. The fatty acids obtained are eco-friendly, bio-degradable and non-toxic. Due to technical, economic and environmental benefits, we have conducted several research projects to develop various chemicals from used cooking oil for oil and gas field applications. Fatty acid-based products mainly used in drilling fluids as lubricants to reduce torque and drag for water-based mud. In case of oil-based mud systems, fatty acid derived products are used as emulsifiers, wetting agents and rheology modifiers. However, these products have been either mixture of fatty acids and their derivatives or only derivatives of fatty acids. In our study, we have used the mixture of fatty acids obtained from chemical conversion of UCO for applications as lubricant for water-based mud and emulsifier and rheology modifier for invert emulsion oil-based mud systems. This paper describes the chemicals process for converting used cooking oil to fatty acids by base hydrolysis reaction in the first section. Application of synthesized fatty acids for water-based and oil-based mud formulation as lubricants, emulsifiers and rheology modifiers have been discussed in the second part of the paper.
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Ramasamy, Jothibasu, und Mohammad K. Arfaj. „Sustainable and Green Drilling Fluid Additives Development“. In Offshore Technology Conference Asia. OTC, 2022. http://dx.doi.org/10.4043/31350-ms.
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Abstract Oil and gas drilling requires several components work simultaneously to ensure smooth and safe drilling. Drilling fluid or mud is an inseparable part of drilling oil and gas wells and circulated through out theh drilling operation. Drilling fluid contains a variety of additives or chemicals to provide various properties to drilling fluid namely viscosity, fluid loss control, emulsion stability, lubricity, etc. Developing environment friendly chemicals to provide the above-mentioned drilling fluid properties is a significant step taken towards sustainability and reducing carbon footprint besides suitability for aquifers and offshore environments. Several fatty acid-based chemicals used in drilling fluids as fatty acids offer eco-friendly and bio-degradable properties besides required drilling fluid properties. Vegatable oil contains triglycerides which is a potential source of fatty acids and their derivatives. Waste vegetable oil (WVO) provides a perpetual and sustainable source of raw material for various types of eco-friendly additives development. Waste vegetable oil is subjected to simple chemical modification of base hydrolysis process and mixtures of fatty acids have been obtained after finishing a sequence of clean-up process of reaction mixture. The fatty acids obtained are environment-friendly, bio-degradable and non-toxic. Due to technical, economic and environmental advantages of products derived from waste vegetable oils, we have undertaken several research projects to produce various chemicals from waste vegetable oil for oil and gas field applications. Fatty acid-based products mainly used in drilling fluids as lubricants to reduce torque and drag for water-based mud. In case of oil-based mud systems, fatty acid derived products are used as emulsifiers, wetting agents and rheology modifiers. However, these products have been either mixture of fatty acids and their derivatives or only derivatives of fatty acids. In our study, we have used the mixture of fatty acids obtained from chemical conversion of WVO for applications as lubricant for water-based mud and emulsifier and rheology modifier for invert emulsion oil-based mud systems. In this paper, we described the chemicals process for converting waste vegetable oil to fatty acids by base hydrolysis reaction in the first section. Application of synthesized fatty acids for water-based and oil-based mud formulation as lubricants, emulsifiers and rheology modifiers have been discussed in the second part of the paper.
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Kulshreshtha, Yask, Philip J. Vardon, Gabrie Meesters, Mark C. M. van Loosdrecht, Nelson J. A. Mota und Henk M. Jonkers. „What Makes Cow-Dung Stabilised Earthen Block Water-Resistant“. In 4th International Conference on Bio-Based Building Materials. Switzerland: Trans Tech Publications Ltd, 2022. http://dx.doi.org/10.4028/www.scientific.net/cta.1.540.
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The water-resistance of cow-dung has made it a widely used stabiliser in traditional earthen structures in several Asian and African countries. Multiple studies have shown an improvement in water-resistance with the addition of cow-dung, but none provides insight into this behaviour. The present study investigates the water-resistance behaviour of cow-dung stabilised earthen blocks through an extensive experimental programme to identify and characterise the components of cow-dung responsible for its water-resistance. Fresh cow-dung was collected and separated into fibres (>63 μm), medium-sized microbial aggregates (1-63 μm) and small-sized microbial aggregates (0.5-7 μm). Each component was mixed with soil and samples were prepared at different water contents (optimum water content corresponding to the highest dry density and water content higher than optimum) and compacted with 2.5 MPa force to prepare compressed blocks. The water-resistance of these blocks was evaluated through the immersion and modified drip/rain test. It was found that the small-sized microbial aggregates are almost entirely responsible for water-resistance behaviour of cow-dung stabilised earthen blocks. Small-sized microbial aggregates were further characterised by gas chromatography, mercury intrusion porosimetry, N2- BET surface area, zeta potential measurement and electron microscopy. The results indicate that the small-sized microbial aggregates are composed of clay-sized negatively charged particles that are rich in fatty acids. The hydrophobicity of these particles is hypothesised to be responsible for water-resistance behaviour. These insights are further used to produce stabilised blocks that performed at least 30 times better than the unstabilised blocks in both water-resistance tests. The study concludes with practical recommendations for the use of wet cow-dung over dry cow-dung and a reduction of fibre content to increase the water-resistance of earthen blocks.
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Eichenauer, Sabrina, Bernd Weber und Ernst A. Stadlbauer. „Thermochemical Processing of Animal Fat and Meat and Bone Meal to Hydrocarbon Based Fuels“. In ASME 2015 9th International Conference on Energy Sustainability collocated with the ASME 2015 Power Conference, the ASME 2015 13th International Conference on Fuel Cell Science, Engineering and Technology, and the ASME 2015 Nuclear Forum. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/es2015-49197.
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The results of the study at hand may have implications for treatment of grease, lipid fractions, free fatty acids (FFA) and salts of FFA extracted from wastes of food industry, bio-refineries or sewage sludge as well as contaminated lipid containing forage. The goal of the study is, to prevent such contaminated wastes from entering the food chain. The following ways of treatment are proposed. Thermal conversion of waste fats from rendering plants or lipids in the presence of aluminosilicates of the zeolite family produce hydrocarbons with net calorific values in the range of 40–42 MJ/kg. NMR studies show aliphatic hydrocarbons as main product at T = 400°C. The spectrum of products is shifted to alkyl benzenes at T = 550°C. In case of sodium carbonate conversion is achieved in the presence of 5% water at T = 430 ± 20°C yielding mainly a liquid bio-crude with a low acid index, a mixture of non-condensable gases and minor amounts of coke. Rectification of bio-crude from animal fat produces 65.8% of hydrocarbon based bio-diesel and 13.3% of gasoline type hydrocarbons. Distillation curve for bio-diesel is in accordance with DIN EN 490. However, the gasoline fraction lacks low boiling hydrocarbons indicating the necessity for technical improvements of condensers. Sodium carbonate is found to be effective as well as being relatively inexpensive compared to zeolite catalysts. Finally, successful conversion of meat and bone meal to biochar is proved by solid-state 13C-NMR.
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Caillol, Sylvain. „Plant oil based radically polymerizable monomers for sustainable polymers“. In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/kypx2569.
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We have focuses our studies on the synthesis of novel biobased monomers designed for free radical polymerization which could increase the biomass carbon content pursuing to equal or improve the performance of existing polymers from non-renewable sources. Cardanol, which is a natural phenolic oil, is issued from Cashew Nutshell Liquid (CNSL), a non-edible renewable resource, co-produced from cashew industry in large commercial volumes (1Mt p.a.). Cardanol is non-toxic and particularly suitable for the addition of aromatic renewable resources in polymers and materials. We recently reported various routes for the synthesis of di- and poly-functional building blocks derived from cardanol thereafter used in polymer syntheses. We especially synthesized a new radically polymerizable cardanol-derived monomer. Hence, we synthesized cardanol-based aromatic latex by radical aqueous emulsion (and miniemulsion) polymerization. We also synthesized UV-reactive cardanol-derived latex for styrene-free coating applications.
Vegetable oils and their fatty acids (FAs) derivatives have become the most promising alternative solution to design performant bio-based polymers. However, considering the poor reactivity of the internal unsaturation of FAs through radical process, most currently available synthesis of monomers reported in literature are limited to polycondensation. Therefore, the objective of our work was to synthesize monomers from fatty acids bearing reactive function through radical process and evaluate their resulting methacrylate polymers as viscosity modifiers in various oils such as mineral or vegetable oils.
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Obuebite, A., und O. O. Okwonna. „Preliminary Assessment of Terminalia Mantaly Gum Exudate as a GreenScale Inhibitor“. In SPE Nigeria Annual International Conference and Exhibition. SPE, 2024. http://dx.doi.org/10.2118/221793-ms.
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Abstract The study explores the potential of Terminalia mantaly gum as a sustainable, effective inhibitor of barium sulfate scale. The use of green materials has garnered attention as a promising natural compound for industrial processes. Scale formation, a pervasive issue in oil production and water treatment, leads to reduced efficiency and increased maintenance costscaused by blockages in pipelines, oil wells etc. However, the use of scale inhibitors has been used for the control of various scale types including barium sulfate scale. Terminalia mantaly gum, a natural polysaccharide, with its abundance, bio-degradable and eco-friendly characteristics aligns with the growing global emphasis on sustainable and green technologies. The gum exudate was extracted from the bark of a Terminalia mantalytree. The preliminary analysis of the scale- inhibitory effect of terminalia gum was evaluated using Thermogravimetric analysis (TGA),X-ray diffraction(XRD), Fourier-transform-infrared spectroscopy (FTIR), and Gas chromatography-mass spectrometry (GC-MS) to analyze their crystal structure, thermal stability, identify and quantify the chemical concentration of the compounds present. Results showed an onset degradation at 315.5 ˚C temperature with a sudden decrease in mass of the sample at a calcination temperature of 560 ˚C. The average crystal size was observed to be twice that of synthetic gum with a high peak intensity (8.45). The FTIR spectra showed a high peak intensity, and symmetrical vibration of the O-H bond which is characteristic of glucoside ring. The chromatogram identified seven compounds linked to a functional group with the major constituent being 9-octadecenoic acid methyl ester at a peak of 63.52 %, indicating that fatty acids are the dominant constituents inTerminalia mantalygum. Its high compatibility with diverse water compositions makes it a potential solution for scale inhibition.The study has shown that Terminalia mantalygum is a viable, eco-conscious option for mitigating scales based on its chemical composition, and crystalline structure, though less efficient at temperatures above 300˚C.
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Rahayu, Sri, Supriyatin und Adiati Bintari. „Activated carbon-based bio-adsorbent for reducing free fatty acid number of cooking oil“. In THE 9TH INTERNATIONAL CONFERENCE ON GLOBAL RESOURCE CONSERVATION (ICGRC) AND AJI FROM RITSUMEIKAN UNIVERSITY. Author(s), 2018. http://dx.doi.org/10.1063/1.5061897.
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Catalanotti, E., K. J. Hughes, M. Pourkashanian, I. Uryga-Bugajska und A. Williams. „Development of a High Temperature Oxidation Mechanism for Bio-Aviation Fuels“. In ASME 2008 International Mechanical Engineering Congress and Exposition. ASMEDC, 2008. http://dx.doi.org/10.1115/imece2008-68667.
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Almost all current civil and military aviation around the world use a kerosene-type fuel. However one of the alternatives is to use a mixture of petrochemicals and biofuel, especially methyl esters derived from vegetable oil (Fatty Acid Methyl Esters, FAMEs) that given their properties appear to be one of the most suitable for Aviation fuels. Studies were conducted to develop a fundamental and detailed reaction mechanism for the combustion of bio-aviation fuel through a combination of the existing kerosene based reaction mechanism developed previously by the authors (Aviation Fuel Reaction Mechanism v1.1), along with published chemical kinetic mechanisms for methylbutanoate (MB). Methylbutanoate is the simplest FAME that exhibits similar patterns of reactivity to FAME’s of longer carbon chain length typical of those derived from vegetable oils, furthermore it has been the subject of several studies to provide chemical kinetic mechanisms to predict its oxidation behavior. Evaluations of the combined reaction mechanism have been performed using CHEMKIN™ and similar software simulating high temperature/pressure conditions. A comparison between the oxidation processes of the Kerosene and Bio-Aviation fuel was carried out, along with sensitivity analysis to provide insight into some of the differences observed. A similar behaviour was observed for blends of 20%MB/80%Kerosene in the combustion conditions studied, indicating that combustion in current aircraft engines would not be adversely affected by using such a blend.
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Murali Krishna, B., und J. M. Mallikarjuna. „Renewable Biodiesel From CSO: A Fuel Option for Diesel Engines“. In ASME 2006 International Solar Energy Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/isec2006-99051.
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The petroleum-based fuels are limited reserve fuels, with our present known reserves and the growing rate of consumption, it is feared that they are not going to last long. These finite resources of petroleum and highly concentrated in certain regions of the world has given rise to frequent disruptions and uncertainties in its supply and as well as price. This situation has created a problem to increase the prices of these oils. The growing dependence on oil has created great scarcities and hardships with serious economic imbalance. A part from the problem of fast vanishing reserves, Petroleum fueled vehicles discharge significant amount of pollutants. In view of these problems attempts must be made to develop the technology of alternate clean burning fuels. The alternative, which satisfies all these requirements, is bio-diesel. Bio-diesel is methyl or ethyl ester of fatty acid made from virgin or used vegetable oils (both edible and non-edible) and animal fat, by converting the triglyceride oils to methyl (or ethyl) esters with a process known as transesterification. Bio-fuels are important now and offer increase in potential for the future. This paper consists two phases. The phase one dealt with preparation of bio-diesel from Cotton Seed Oil (C.S.O), which is available at cheaper price, as it is byproduct from cotton industries. Its properties were determined experimentally and compared with the conventional diesel fuel. The second phase dealt with conduction of experiments on a single cylinder, 4-stroke, direct injection Diesel Engine without modifications at constant speed 1500 rpm for various loads using 100% bio-diesel and conventional diesel fuel. It noticed that, the performance of the engine is not severely deviated by the substituted renewable biodiesel inaddition considerable decrease in smoke level. It is concluding that the biodiesel is superior fuel from the environmental and performance point of view, addition to this reducing the import of oil and consequentially improving energy security as a renewable alternate fuel.
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Niemi, Seppo, Jukka Kiijärvi, Mika Laurén und Erkki Hiltunen. „Injection Pressures of a Bio-Oil Driven Non-Road Diesel Engine: Experiments and Simulations“. In ASME 2012 11th Biennial Conference on Engineering Systems Design and Analysis. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/esda2012-82710.
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The depletion of global crude oil reserves, increases in fossil fuel prices and environmental issues have encouraged the search for and study of bio-derived fuels. For years, fatty acid methyl esters (FAME) have already been used successfully. High-quality hydrogenated vegetable oil and Fischer-Tropsch biofuels have also been developed. Fuel refining processes, however, consume energy increasing CO2 emissions. For profitability reasons, large-scale industrial production is also required. Several distributed energy producers are instead willing to utilize various local waste materials as fuel feedstock. The target is local fuel production without any complicated manufacturing processes. Crude bio-oils are therefore also interesting fuel options, in particular for medium-speed diesel engines capable of burning such bio-oils without any major problems. Nevertheless, waste-derived crude bio-oils have also been studied in Finland in high-speed non-road diesel engines. One option has been mustard seed oil (MSO). Mustard has been cultivated in fallow fields. Non-food mustard seeds have been used for fuel manufacturing. In the performed studies with MSO, the exhaust smoke and HC emissions decreased, NOx remained approximately constant, and the thermal efficiency was competitive compared with operation on ordinary diesel fuel oil (DFO). The number of exhaust particles tended, however, to increase and deposits were formed in the combustion chamber, particularly if the engine was also run at low loads with MSO. On the whole, the results were so promising that deeper analyses of engine operation with MSO were considered reasonable. The kinematic viscosity of crude bio-oils is much higher than that of FAMEs or DFO. Consequently, the injection pressure tends to increase especially at the injection pump side of an in-line injection pump system. The flow characteristics of crude bio-oil also differ from those of DFO in the high-pressure pipe. With bio-oil, the flow seems to be laminar. The bulk modulus of bio-oils is also different from that of DFO affecting the rate of the injection pressure rise. In the present study, a turbocharged, inter-cooled direct-injection non-road diesel engine was driven with a mixture of MSO (95%) and rape seed methyl ester (RME, 5%), and standard DFO. The engine was equipped with an in-line injection pump. First, the injection pressures at pump and injector ends of the high-pressure injection pipe were measured for both fuels as a function of crank angle. Furthermore, a model was created for the injection system based on the method of characteristics. Free software called Scilab was adopted for numerical simulation of the model. Despite a few limitations in the built model, the results showed clear trends and the model can be used to predict changes in the fuel injection process when the fuel is changed.
Berichte der Organisationen zum Thema "Bio-Based fatty acids"
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Mattie, David R., Jonathon M. Hurley, Edward S. Riccio und Teresa R. Sterner. Acute Dermal Irritation Study and Salmonella-Escherichia coli/Microsome Plate Incorporation Assay of Hydroprocessed Esters and Fatty Acids (HEFA) Bio-Based Jet Fuels. Fort Belvoir, VA: Defense Technical Information Center, Januar 2013. http://dx.doi.org/10.21236/ada584649.
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Wong, Brian A., William R. Howard, Teresa R. Sterner, Michelle W. Elliott und David R. Mattie. 90-Day Inhalation Toxicity Study of Hydroprocessed Esters and Fatty Acids (HEFA) Bio-Based Jet Fuel in Rats (Rattus norvegicus) with Neurotoxicity Testing and Genotoxicity Assay. Fort Belvoir, VA: Defense Technical Information Center, Juni 2013. http://dx.doi.org/10.21236/ada596005.
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Glazer, Itamar, Alice Churchill, Galina Gindin und Michael Samish. Genomic and Organismal Studies to Elucidate the Mechanisms of Infectivity of Entomopathogenic Fungi to Ticks. United States Department of Agriculture, Januar 2013. http://dx.doi.org/10.32747/2013.7593382.bard.
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The overall goal of this research was to elucidate the factors affecting early development of Metarhizium spp. (previously named M. anisopliae) on ticks or tick cuticle extracts and the molecular basis of these early infection processes. The original objectives were: 1. Characterize the pre-penetration events (adhesion, germination and appressorium formation) of spores of M. anisopliae strains with high or low virulence during tick infection. 2. Create GFP-expressing strains of M. anisopliae tick pathogens having high and low virulence to compare their progress of infection by microscopy. 3. Use microarray analyses, primarily with existing M. anisopliae EST sequences in GenBank, to identify and characterize fungal genes whose expression is regulated in response to host cuticle extracts. Objective 3 was later modified (as approved by BARD) to use RNAseq to characterize the early stages of fungal gene expression during infection of intact host cuticles. This new method provides a massively larger and more informative dataset and allows us to take advantage of a) recently published genomes of Metarhizium robertsii and M. acridum for RNAseq data analysis, and b) newly developed and highly efficient cDNA sequencing technologies that are relatively low cost and, therefore, allow deep sequencing of multiple transcriptome samples. We examined pre-penetration and penetration events that differentiate high and low virulence strains of Metarhizium spp., focusing on spore adhesion, germination, appressorium formation, and penetration of tick integuments. Initiation of fungal infection was compared on susceptible and resistant tick species at different tick developmental stages. In vitro studies comparing the effects of protein and fatty acid profiles from tick cuticle extracts demonstrated that resistant tick cuticles contain higher concentrations of specific lipids that inhibit fungal development than do susceptible tick cuticles, suggesting one mechanism of Ixodidae resistance to fungal entomopathogens (Objective 1). We used molecular markers to determine that the three M. anisopliae strains from Israel that we studied actually were three distinct species. M. brunneum is highly virulent against the tick Rhipicephalus annulatus, M. pingshaense and M. robertsii are intermediate in virulence, and M. majus is of low virulence. We transformed all four Metarhizium species to express GFP and used them in pathogenicity assays against diverse tick species. Key findings were that a) resistant ticks inhibit Metarhizium infection prior to hemocoel invasion by reducing fungal viability on the cuticle surface (Objective 2), as was supported by the in vitro studies of Objective 1, and b) Metarhizium kills susceptible ticks after cuticle penetration but prior to hemocoel colonization. Transcriptome studies of the most virulent species, M. brunneum, are in progress and include analyses of ungerminated conidia and conidia germination and development on a low nutrient medium or on susceptible R. annulatus exoskeleton (Objective 3). We anticipate these studies will contribute to identifying fungal genetic factors that increase virulence and speed of kill and may help reveal tick chemistries that could be included in biocontrol formulations to increase efficacy. Methodologies developed to screen tick cuticle extracts for ability to support conidia germination and development may help in the selection of wild fungi with increased virulence against resistant ticks. The overall knowledge gained should contribute not only to the improvement of tick control but also to the control of other blood-sucking arthropods and related plant pests. Use of bio-based agents for controlling arthropods will contribute to a healthier, more sustainable environment and serve a growing number of organic food farmers.