Academic literature on the topic 'Wax ester synthesis'
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Journal articles on the topic "Wax ester synthesis"
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Kawiński, Adam, Magdalena Miklaszewska, Szymon Stelter, Bartosz Głąb, and Antoni Banaś. "Lipases of germinating jojoba seeds efficiently hydrolyze triacylglycerols and wax esters and display wax ester-synthesizing activity." BMC Plant Biology 21, no. 1 (2021): 50. https://doi.org/10.1186/s12870-020-02823-4.
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<strong>Background: </strong> <i>Simmondsia chinensis</i> (jojoba) is the only plant known to store wax esters instead of triacylglycerols in its seeds. Wax esters are composed of very-long-chain monounsaturated fatty acids and fatty alcohols and constitute up to 60% of the jojoba seed weight. During jojoba germination, the first step of wax ester mobilization is catalyzed by lipases. To date, none of the jojoba lipase-encoding genes have been cloned and characterized. In this study, we monitored mobilization of storage reserves during germination of jojoba seeds and performed detailed characterization of the jojoba lipases using microsomal fractions isolated from germinating seeds.<strong>Results: </strong>During 26 days of germination, we observed a 60–70% decrease in wax ester content in the seeds, which was accompanied by the reduction of oleosin amounts and increase in glucose content. The activity of jojoba lipases in the seed microsomal fractions increased in the first 50 days of germination. The enzymes showed higher activity towards triacylglycerols than towards wax esters. The maximum lipase activity was observed at 60 °C and pH around 7 for triacylglycerols and 6.5–8 for wax esters. The enzyme efficiently hydrolyzed various wax esters containing saturated and unsaturated acyl and alcohol moieties. We also demonstrated that jojoba lipases possess wax ester-synthesizing activity when free fatty alcohols and different acyl donors, including triacylglycerols and free fatty acids, are used as substrates. For esterification reactions, the enzyme utilized both saturated and unsaturated fatty alcohols, with the preference towards long chain and very long chain compounds.<strong>Conclusions: </strong>In in vitro assays, jojoba lipases catalyzed hydrolysis of triacylglycerols and different wax esters in a broad range of temperatures. In addition, the enzymes had the ability to synthesize wax esters in the backward reaction. Our data suggest that jojoba lipases may be more similar to other plant lipases than previously assumed.
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Yu, Dan, Ellen Hornung, Tim Iven, and Ivo Feussner. "High-level accumulation of oleyl oleate in plant seed oil by abundant supply of oleic acid substrates to efficient wax ester synthesis enzymes." Biotechnology for Biofuels 11, no. 1 (2018): 53. https://doi.org/10.1186/s13068-018-1057-4.
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<strong>Background: </strong>Biotechnology enables the production of high-valued industrial feedstocks from plant seed oil. The plant-derived wax esters with long-chain monounsaturated acyl moieties, like oleyl oleate, have favorite properties for lubrication. For biosynthesis of wax esters using acyl-CoA substrates, expressions of a fatty acyl reductase (FAR) and a wax synthase (WS) in seeds are sufficient.<strong>Results: </strong>For optimization of the enzymatic activity and subcellular localization of wax ester synthesis enzymes, two fusion proteins were created, which showed wax ester-forming activities in <i>Saccharomyces cerevisiae</i>. To promote the formation of oleyl oleate in seed oil, WSs from <i>Acinetobactor baylyi</i> (<i>Ab</i>WSD1) and <i>Marinobacter aquaeolei</i> (<i>Ma</i>WS2), as well as the two created fusion proteins were tested in Arabidopsis to evaluate their abilities and substrate preference for wax ester production. The tested seven enzyme combinations resulted in different yields and compositions of wax esters. Expression of a FAR of <i>Marinobacter aquaeolei</i> (<i>Ma</i>FAR) with <i>Ab</i>WSD1 or <i>Ma</i>WS2 led to a high incorporation of C<sub>18</sub> substrates in wax esters. The <i>Ma</i>FAR/TM<i>Mm</i>AWAT2-<i>Ab</i>WSD1 combination resulted in the incorporation of more C<sub>18:1</sub> alcohol and C<sub>18:0</sub> acyl moieties into wax esters compared with <i>Ma</i>FAR/<i>Ab</i>WSD1. The fusion protein of a WS from <i>Simmondsia chinensis</i> (<i>Sc</i>WS) with MaFAR exhibited higher specificity toward C<sub>20:1</sub> substrates in preference to C<sub>18:1</sub> substrates. Expression of <i>Ma</i>FAR/<i>Ab</i>WSD1 in the Arabidopsis <i>fad2 fae1</i> double mutant resulted in the accumulation of oleyl oleate (18:1/18:1) in up to 62 mol% of total wax esters in seed oil, which was much higher than the 15 mol% reached by <i>Ma</i>FAR/<i>Ab</i>WSD1 in Arabidopsis Col-0 background. In order to increase the level of oleyl oleate in seed oil of <i>Camelina</i>, lines expressing <i>Ma</i>FAR/<i>Sc</i>WS were crossed with a transgenic high oleate line. The resulting plants accumulated up to >40 mg g seed<sup>−1</sup> of wax esters, containing 27–34 mol% oleyl oleate.<strong>Conclusions: </strong>The overall yields and the compositions of wax esters can be strongly affected by the availability of acyl-CoA substrates and to a lesser extent, by the characteristics of wax ester synthesis enzymes. For synthesis of oleyl oleate in plant seed oil, appropriate wax ester synthesis enzymes with high catalytic efficiency and desired substrate specificity should be expressed in plant cells; meanwhile, high levels of oleic acid-derived substrates need to be supplied to these enzymes by modifying the fatty acid profile of developing seeds.
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Ishige, Takeru, Akio Tani, Keiji Takabe, Kazunori Kawasaki, Yasuyoshi Sakai, and Nobuo Kato. "Wax Ester Production from n-Alkanes by Acinetobacter sp. Strain M-1: Ultrastructure of Cellular Inclusions and Role of Acyl Coenzyme A Reductase." Applied and Environmental Microbiology 68, no. 3 (2002): 1192–95. http://dx.doi.org/10.1128/aem.68.3.1192-1195.2002.
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ABSTRACT Acinetobacter sp. strain M-1 accumulated a large amount of wax esters from an n-alkane under nitrogen-limiting conditions. Under the optimized conditions with n-hexadecane as the substrate, the amount of hexadecyl hexadecanoate in the cells reached 0.17 g/g of cells (dry weight). Electron microscopic analysis revealed that multilayered disk-shaped intracellular inclusions were formed concomitant with wax ester formation. The contribution of acyl-CoA reductase to wax ester synthesis was evaluated by gene disruption analysis.
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Xu, Juntao, Renwei Zhang, Changsheng Liu, Fang Wang, Kaili Nie, and Li Deng. "The Application of a Rotating Packed Bed Reactor for the Synthesis of High Viscosity Wax Ester." Journal of Biobased Materials and Bioenergy 15, no. 3 (2021): 421–27. http://dx.doi.org/10.1166/jbmb.2021.2052.
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Wax esters are high value-added products and widely used in a broad range of commercial fields. The enzymatic synthesis of wax ester from plant oil is more attractive than the traditional chemical method due to being environmental-friendly and limiting the use of hazardous chemicals. However, the high mass transfer resistance from the high viscous substrate leads to a low conversion and long reaction time in the continues stirred tank reactor (CSTR). The rotating packed bed reactor (RPBR) offers high mass transfer and can be used to enhance the enzymatic wax ester synthesis process. From the results, it could be concluded that the mass transfer was enhanced with the optimization of the centrifugal factor of the RPBR. Under the optimal process conditions, the wax ester yield of 96.4% was obtained after 4 hours reaction, and the half-life of the catalyst corresponded with 64 hours, while nine batches achieved of yields above 90%. The investigation proved that the RPBR is an attractive and effective reactor for heterogeneous bio-catalysis in high viscosity of 7.39~12.27 Cst at 40 °C.
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Lenneman, Eric M., Janet M. Ohlert, Nagendra P. Palani, and Brett M. Barney. "Fatty Alcohols for Wax Esters in Marinobacter aquaeolei VT8: Two Optional Routes in the Wax Biosynthesis Pathway." Applied and Environmental Microbiology 79, no. 22 (2013): 7055–62. http://dx.doi.org/10.1128/aem.02420-13.
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ABSTRACTThe biosynthesis of wax esters in bacteria is accomplished by a unique pathway that combines a fatty alcohol and a fatty acyl coenzyme A substrate. Previousin vitroenzymatic studies indicated that two different enzymes could be involved in the synthesis of the required fatty alcohol inMarinobacter aquaeoleiVT8. In this study, we demonstrate through a series of gene deletions and transcriptional analysis that either enzyme is capable of fulfilling the role of providing the fatty alcohol required for wax ester biosynthesisin vivo, but evolution has clearly selected one of these, a previously characterized fatty aldehyde reductase, as the preferred enzyme to perform this reaction under typical wax ester-accumulating conditions. These results complement previousin vitrostudies and provide the first glimpse into the role of each enzymein vivoin the native organism.
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MANKURA, Mitsumasa, and Mitsu KAYAMA. "Wax Ester Synthesis by Carp Hepatopancreas Preparation." Journal of Japan Oil Chemists' Society 36, no. 4 (1987): 244–53. http://dx.doi.org/10.5650/jos1956.36.244.
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Aizouq, Mohammed, Helga Peisker, Katharina Gutbrod, Michael Melzer, Georg Hölzl, and Peter Dörmann. "Triacylglycerol and phytyl ester synthesis inSynechocystissp. PCC6803." Proceedings of the National Academy of Sciences 117, no. 11 (2020): 6216–22. http://dx.doi.org/10.1073/pnas.1915930117.
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Cyanobacteria are unicellular prokaryotic algae that perform oxygenic photosynthesis, similar to plants. The cells harbor thylakoid membranes composed of lipids related to those of chloroplasts in plants to accommodate the complexes of photosynthesis. The occurrence of storage lipids, including triacylglycerol or wax esters, which are found in plants, animals, and some bacteria, nevertheless remained unclear in cyanobacteria. We show here that the cyanobacteriumSynechocystissp. PCC6803 accumulates both triacylglycerol and wax esters (fatty acid phytyl esters). Phytyl esters accumulate in higher levels under abiotic stress conditions. The analysis of an insertional mutant revealed that the acyltransferase slr2103, with sequence similarity to plant esterase/lipase/thioesterase (ELT) proteins, is essential for triacylglycerol and phytyl ester synthesis inSynechocystis. The recombinant slr2103 enzyme showed acyltransferase activity with phytol and diacylglycerol, thus producing phytyl esters and triacylglycerol. Acyl-CoA thioesters were the preferred acyl donors, while acyl-ACP (acyl carrier protein), free fatty acids, or galactolipid-bound fatty acids were poor substrates. The slr2103 protein sequence is unrelated to acyltransferases from bacteria (AtfA) or plants (DGAT1, DGAT2, PDAT), and therefore establishes an independent group of bacterial acyltransferases involved in triacylglycerol and wax ester synthesis. The identification of the geneslr2103responsible for triacylglycerol synthesis in cyanobacteria opens the possibility of using prokaryotic photosynthetic cells in biotechnological applications.
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Holtzapple, Erik, and Claudia Schmidt-Dannert. "Biosynthesis of Isoprenoid Wax Ester in Marinobacter hydrocarbonoclasticus DSM 8798: Identification and Characterization of Isoprenoid Coenzyme A Synthetase and Wax Ester Synthases." Journal of Bacteriology 189, no. 10 (2007): 3804–12. http://dx.doi.org/10.1128/jb.01932-06.
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ABSTRACT Marinobacter hydrocarbonoclasticus DSM 8798 has been reported to synthesize isoprenoid wax ester storage compounds when grown on phytol as the sole carbon source under limiting nitrogen and/or phosphorous conditions. We hypothesized that isoprenoid wax ester synthesis involves (i) activation of an isoprenoid fatty acid by a coenzyme A (CoA) synthetase and (ii) ester bond formation between an isoprenoid alcohol and isoprenoyl-CoA catalyzed, most likely, by an isoprenoid wax ester synthase similar to an acyl wax ester synthase, wax ester synthase/diacylglycerol acyltransferase (WS/DGAT), recently described from Acinetobacter sp. strain ADP1. We used the recently released rough draft genome sequence of a closely related strain, M. aquaeolei VT8, to search for WS/DGAT and acyl-CoA synthetase candidate genes. The sequence information from putative WS/DGAT and acyl-CoA synthetase genes identified in this strain was used to clone homologues from the isoprenoid wax ester synthesizing Marinobacter strain. The activities of the recombinant enzymes were characterized, and two new isoprenoid wax ester synthases capable of synthesizing isoprenoid ester and acyl/isoprenoid hybrid ester in vitro were identified along with an isoprenoid-specific CoA synthetase. One of the Marinobacter wax ester synthases displays several orders of magnitude higher activity toward acyl substrates than any previously characterized acyl-WS and may reflect adaptations to available carbon sources in their environments.
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Gunawan, Erin Ryantin, and Dedy Suhendra. "FOUR-FACTOR RESPONSE SURFACE OPTIMIZATION OF THE ENZYMATIC SYNTHESIS OF WAX ESTER FROM PALM KERNEL OIL." Indonesian Journal of Chemistry 8, no. 1 (2010): 83–90. http://dx.doi.org/10.22146/ijc.21653.
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The synthesis of wax ester using refined, bleached and deodorized (RBD) palm kernel oil (PKO) and oley alcohol catalyzed by Lipozyme IM was carried out. Response surface methodology (RSM) based on a five-level, four-factor central composite rotatable design (CCRD) was used to evaluate the interactive effects of synthesis, of reaction time (5-20 h), temperature (20-50 oC), amount of enzyme (0.1-0.2 g) and substrate molar ratio (palm kernel oil to oleyl alcohol, 1:1-1:5) on the percentage yield of wax esters. The optimum condition conditions derived via RSM were reaction time 8.46 h, temperature 44.4 oC, amount of enzyme 0.182 g, substrate molar ratio 1 to 3.7. The actual experimental yield was 92.9 % under optimum condition, which good accordance to the maximum predicted value of 92.4 %. Keywords: response surface methodology, central composite rotatable design, palm kernel oil, lipozyme, alcoholysis, wax ester
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Gao, Xiang, Yuandan Zhang, Zhe Li, Xinmin Wang, and Yingna Du. "Study on synthesis and properties of polyacrylate wax inhibitor." Journal of Physics: Conference Series 2723, no. 1 (2024): 012013. http://dx.doi.org/10.1088/1742-6596/2723/1/012013.
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Abstract Synthesis and properties of polyacrylate ester paraffin inhibitior based on polyacrylate ester start from dodecanol, tetradecanol, hexadecanol, octadecanol respectively were introduced in this paper. Hexadecyl polyacrylic showed the most potent paraffin inhibition, and then the optimum reaction condition of it was ascertained. The percentage inhibition of hexadecyl polyacrylic, synthesized under the optimized conditions, reached to 79.3%. Then crosslinked polyacrylate ester paraffin inhibitiors were synthesized and screened by static wax precipitation experiment, and find the percentage inhibition of crosslinked hexadecyl polyacrylic reached to 88.4%.
Dissertations / Theses on the topic "Wax ester synthesis"
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Taher, Salam Ghafour. "Synthesis of myobacterial wax esters and related compounds." Thesis, Bangor University, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.664599.
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Mycobacteria are present in a wide range of environments. They contain characteristic complex mixtures of mycolic acids in the cell wall together with other lipids. The high resistance of mycobacteria to the majority of antibiotics, therapeutic agents and disinfectants is thought to be related to the unique structure of the mycobacterial cell wall. Mycolic acids are high molecular weight a-alkyl-branched B-hydroxy long chain fatty acids (60-90 carbon atoms). Different species of Mycobacteria may produce different classes of mycolic acids including a-, methoxy, keto, and wax ester mycolic acids, each present as mixtures of homologues. These may contain different functional groups such as ester, keto, methoxy, hydroxyl, and alkene. The most reported lipids present in the cell wall are sugar esters, e.g mycolyl trehalose esters. These mycolic acids and mycolyl trehalose esters show very interesting toxic and immunological properties; these offer considerable potential for application in the detection, control, and treatment of mycobacterial infection, and also in developing sensors for detection of disease. This study will seek to explore these potentials. This project involved the synthesis of several mycolic acids, wax esters and trehalose esters. The biological activities of these synthetic compounds would be studied, particularly their suitability as specific antigens to detect mycobacterial infections in serodiagnostic assays. The objectives of the project are discussed in four parts. The first part of this project involved the first synthesis of wax ester (A) and its corresponding ω-carboxymycolic acid (B), one component of the complex mixture isolated from Mycobacterium avium. Once the synthesis had been optimised, synthesis of the wax ester (C) and its corresponding ω-carboxymycolic acid (D) were also achieved, the latter compounds being isolated from Mycobacterium gordonae. In addition the wax ester (E) was also prepared introducing longer chain lengths than the natural wax ester. This was to study whether or not the chain length has any effect on the biological activities.
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Knox, T. "Synthesis of long chain esters by a fungal cell-bound enzyme." Thesis, University of the West of Scotland, 1985. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370509.
Full textBook chapters on the topic "Wax ester synthesis"
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Taber, Douglass F. "Functional Group Protection: The Kraus Synthesis of Bauhinoxepin J." In Organic Synthesis. Oxford University Press, 2013. http://dx.doi.org/10.1093/oso/9780199965724.003.0013.
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Amos B. Smith III of the University of Pennsylvania found (Synlett 2009, 3131) that the advanced SAMP intermediate 1 could be deprotected to 2 without racemization under mild oxidative conditions. Akihiko Ouchi of the National Institute of Advanced Industrial Science and Technology, Tsukuba, showed (Organic Lett. 2009, 11, 4870) that the C-Te of 3 was easily oxidized to the aldehyde 4. Secondary C-Te bonds were converted to ketones. Asit K. Chakraborti of NIPER prepared (J. Org. Chem. 2009, 74, 5967) esters by warming an acid 5 with an alcohol 6 in the presence of acidic silica gel. Gilles Quéléver of Aix-Marseille Université established (Tetrahedron Lett. 2009, 50, 4346) that a cyanomethyl ester 8, readily prepared from the acid, efficiently exchanged with an alcohol 9 to give the ester 10. Martin J. Lear of the National University of Singapore protected (Tetrahedron Lett. 2009, 50, 5267) an alcohol 11 as the p -methoxybenzyl ether 13 under mild conditions (AgOTf/DTBMP) with the new reagent 12 . Isao Kadota of Okayama University selectively removed (Tetrahedron Lett. 2009, 50, 4552) the primary PMB ether from 14 to give 15. Hiromishi Fujioka of Osaka University, starting (Organic Lett. 2009, 11, 5138) from 16, was able to selectively prepare either the primary protected 18 or the secondary protected 19. In other developments (not pictured), Mattie S. M. Timmer and Brendan A. Burkett of Victoria University of Wellington devised (Tetrahedron Lett. 2009, 50, 7199) a convenient preparation for azulene-containing α-keto esters. The distinctively colored protecting group was conveniently removed in the presence of other esters by treatment with o-phenylenediamine. Scott D. Taylor of the University of Waterloo established (J. Org. Chem. 2009, 74, 9406) a robust protocol for converting alcohols to the corresponding protected sulfates. P. Shanthan Rao of the Indian Institute of Chemical Technology, Hyderabad, showed (Tetrahedron Lett. 2009, 50, 7099) that an amine 20 was formylated by warming with formic acid in the presence of ZnCl2. The easily hydrolyzed formamide 21 is readily converted to the corresponding isonitrile. Shiyue Fang of Michigan Technological University selectively monoacylated (Tetrahedron Lett. 2009, 50, 5741) the symmetrical diamine 22 using phenyl esters.
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Taber, Douglass F. "Organic Functional Group Protection." In Organic Synthesis. Oxford University Press, 2013. http://dx.doi.org/10.1093/oso/9780199965724.003.0012.
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Masato Kitamura of Nagoya University investigated (Chemistry Lett. 2009, 38, 188) the Ru-mediated deprotection of allyl ethers such as 1. The same catalyst was effective for the preparation of allyl ethers from the alcohol 2 and allyl alcohol. István E. Markó of the Université Catholique de Louvain showed (Organic Lett. 2009, 11, 2752) that SmI2 effected the reductive cleavage of an aryl ester 3, liberating the alcohol 4. Osamu Onomura of Nagasaki University found (Tetrahedron Lett. 2009, 50, 1466) that catalytic CuCl2 mediated the selective monoallylation of symmetrical diols such as 5. Péter Fügedi of the Hungarian Academy of Sciences, Budapest, observed (Tetrahedron Lett. 2009, 50, 2914) that TMSOTf catalyzed the selective reduction of 7 to the benzyl ether. BH3. NMe2 delivered the opposite regioisomer. Direct amination of an ester has been a long-sought transformation. Vladimir B. Birman of Washington University found (Organic Lett. 2009, 11, 1499) that 1,2,4-triazole 11 in combination with DBU was an effective catalyst for this reaction. Unactivated esters required higher reaction temperatures. Deprotection of amides often requires vigorous conditions, and the product free amines can be challenging to handle. Stefan G. Koenig of Sepracor Chemical Process devised (Organic Lett. 2009, 11, 433) a simple protocol for in situ formation and hydrolysis of the imidoyl chloride from 12 that delivered the amine hydrochloride 13 directly. Remarkably, benzamides are stable under these conditions. Hongmei Li of Merck Process devised (Tetrahedron Lett. 2009, 50, 1010) a related procedure: heating the more reactive trifluoroacetamide 14 with stoichiometric p-toluenesulfonic acid, and isolating the product as the p-toluenesulfonate salt 15. There has been a reluctance to use sulfonamide protecting groups, as they have been thought to be difficult to remove. Göran Hilmersson of the University of Gothenburg established (Organic Lett. 2009, 11, 503) that SmI2 instantaneously deprotected 16. Daniel E. Falvey of the University of Maryland designed (J. Org. Chem. 2009, 74, 3894) the benzyl ester 17, which was readily released under photolysis. Stanislaw Krompiec of the University of Silesia described (Tetrahedron Lett. 2009, 50, 1193) what appears to be a general strategy for the preparation of ortho esters such as 21.
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Taber, Douglass. "Best Synthetic Methods: Reduction." In Organic Synthesis. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199764549.003.0006.
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Jaiwook Park of Pohang University of Science and Technology has developed (Org. Lett. 2007, 9, 3417) a procedure for the preparation of Pd-impregnated magnetic Fe nanoparticles. This effective hydrogenation catalyst was attracted to an external magnet and so was easily separated from the reaction matrix. Duk Keun An of Kangwon National University has found (Chem. Lett. 2007, 36, 886) that by including NaOtBu, Dibal reduction of an ester such as 3 can be made to reliably stop at the aldehyde 4. By using the easily-prepared pentaflurophenyl ester 5, Panagiota Moutevelis-Minakakis of the University of Athens was able to reduce an acid to the alcohol 6. Lionel A. Saudan of Firmenich SA, Geneva has devised (Angew. Chem. Int. Ed. 2007, 46, 7473) a Ru catalyst that will hydrogenate an ester such as 7 to the alcohol 8 without reducing an internal alkene. Norio Sakai of the Tokyo University of Science has established (J. Org. Chem. 2007, 72, 5920) what promises to be a general route to ethers 10, by direct reduction of the corresponding ester 9. Hideo Nagashima of Kyushu University has developed ( Chem. Commun. 2007, 4916) a Ru catalyst that effected selective hydrogenation of an amide 11 to the amine 12 without reducing ketones or esters. Alternatively, Jason S. Tedrow of Amgen Inc., Thousand Oaks, CA has found (J. Org. Chem. 2007, 72, 8870) that a protocol developed by Robert E. Maleczka, Jr. of Michigan State University was effective for reducing an aryl ketone 13 to the corresponding hydrocarbon 14 without reducing the amide. The stereocontrolled reductive amination of cyclic ketones such as 15 has been a continuing challenge. Shawn Cabral of Pfizer, Inc. in Groton, CT has reported (Tetrahedron Lett. 2007, 48, 7134) complementary reagent combinations, leading selectively to either 16 or 17. To control catalytic hydrogenation, it is often desirable to control the H2 supply. John S. McMurray of the University of Texas M. D. Anderson Cancer Center in Houston has shown (J. Org. Chem. 2007, 72, 6599) that Et3SiH is a convenient H2 source. Nitro alkanes add to aldehydes to give nitro alkenes such as 20.
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Taber, Douglass F. "Organocatalyzed C–C Ring Construction: The Hayashi Synthesis of PGE1 Me Ester." In Organic Synthesis. Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780190200794.003.0073.
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Xiaohua Liu and Xiaoming Feng of Sichuan University devised (J. Org. Chem. 2013, 78, 6322) a catalyst that mediated the addition of the ylide 2 to the enone 1 to give 3. Peng-fei Xu of Lanzhou University found (Chem. Commun. 2013, 49, 4625) that the vinyl pyrrole 4 was sufficiently nucleophilic to add to 5, leading to the cyclobutane 6. Albert Moyano of the Universitat de Barcelona added (Eur. J. Org. Chem. 2013, 3103) 8 to the unsaturated aldehyde 7 to give the β-amino acid precursor 9. Eugenia Marqués-López and Mathias Christmann, now at Freie Universität Berlin effected (Synthesis 2013, 45, 1016) the intramolecular Michael cyclization of 10 to give 11. Delong Liu and Wanbin Zhang of Shanghai Jiao Tong University showed (Synthesis 2013, 45, 1612) that 12 and 13 could be combined to give the cyclopentane 14. Ismail Ibrahem and Armando Córdova of Mid Sweden University combined (Angew. Chem. Int. Ed. 2013, 52, 6050) 15 and 16 to give 17, with good control of the quaternary center. Kamal Nain Singh of Panjab University prepared (Synthesis 2013, 45, 1406) a proline-derived sulfoxide that mediated the addition of cyclohexanone 18 to 19. Intramolecular aldehyde alkylation is underdeveloped as a synthetic method. David W.C. MacMillan of Princeton University established (J. Am. Chem. Soc. 2013, 135, 9358) a single-electron transfer variant, cyclizing 21 to 22. Arianna Quintavalla of the University of Bologna effected (Adv. Synth. Catal. 2013, 355, 938) the double addition of nitromethane 24 to 23 to give 25. John Cong-Gui Zhao of the University of Texas at San Antonio reported (Chem. Eur. J. 2013, 19, 1666; J. Org. Chem. 2013, 78, 4153) parallel results (not pictured) with aryl enones as the acceptors. Bor-Cherng Hong of the National Chung Cheng University condensed (Eur. J. Org. Chem. 2013, 2472) 26 with the alcohol 27 to give 28. Again, good control of the quaternary center was observed. Marc C. Kimber of Loughborough University used (J. Org. Chem. 2013, 78, 3476) an organocatalyst to rearrange the prochiral endoperoxide 29 to the hydroxy enone, to which malonate 30 was added to give 31.
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Taber, Douglass. "The Zakarian Synthesis of ( + )-Pinnatoxin A." In Organic Synthesis. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199764549.003.0097.
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( + )-Pinnatoxin A 3, isolated from the shellfish Pinna muricata, is thought to be a calcium channel activator. A key transformation in the synthesis of 3 reported (J. Am. Chem. Soc . 2008, 130, 3774) by Armen Zakarian, now at the University of California, Santa Barbara, was the diastereoselective Claisen rearrangement of 1 to 2. The alcohol portion of ester 1 was derived from the aldehyde 4, prepared from D-ribose. The absolute configuration of the secondary allylic alcohol was established by chiral amino alcohol catalyzed addition of diethyl zinc to the unsaturated aldehyde 5. The acid portion of the ester 1 was prepared from (S)-citronellic acid, by way of the Evans imide 7. Methylation proceeded with high diasterocontrol, to give 8. Functional group manipulation provided the imide 9. Alkylation then led to 10, again with high diastereocontrol. In each case, care had to be taken in the further processing of the α-chiral acyl oxazolidinones. Direct NaBH4 reduction of 8 delivered the primary alcohol. To prepare the acid 10, the alkylated acyl oxazolidinone was hydrolyzed with alkaline hydrogen peroxide. On exposure of the ester 1 to the enantiomerically-pure base 11, rearrangement proceeded with high diastereocontrol, to give the acid 2. This outcome suggests that deprotonation proceeded to give the single geometric form of the enolate, that was then trapped to give specifically the ketene silyl acetal 12. This elegant approach is dependent on both the ester 1 and the base 11 being enantiomerically pure. The carbocyclic ring of pinnatoxin A 3 was assembled by intramolecular aldol condensation of the dialdehyde 11. This outcome was remarkable, in that 11 is readily epimerizable, and might also be susceptible to β-elimination. Note that the while the diol corresponding to 11 could be readily oxidized to 11 under Swern conditions, attempts to oxidize the corresponding hydroxy aldehyde were not fruitful.
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Saeed, Muhammad, Ghulam Mustafa, Faiz Ahmad Joyia, Aneela Shadab, and Aqsa Parvaiz. "Biotechnological Interventions for the Production of Glycerol-Free Biodiesel." In Advanced Biodiesel - Technological Advances, Challenges, and Sustainability Considerations. IntechOpen, 2024. http://dx.doi.org/10.5772/intechopen.108895.
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Advances in plant biotechnology and microbial genetics are speeding up because of the urgent need to provide a steady supply of resources. Growing cost of crude oil is having a negative impact on economies throughout the globe. Just biodiesel and bioethanol have been recognized as viable fossil fuel replacements. Chemical catalysis is primary way to synthesize biodiesel, besides enzymatic and microbial methods also play important role in biodiesel synthesis. These processes may play a significant part in the replacement of petroleum-based diesel in the future. The growth of sustainable, economically feasible biotechnological tools for the synthesis of biodiesel requires strong collaboration among several disciplines. In this age, lipases are the preferred enzymes for producing methyl esters (FAME), which are significant biological objects in biodiesel, from fatty acid esters (FAE) derived from fats and oils. It has also been shown that designed whole-cell microorganisms may directly produce FAE (MicroDiesel). The expensive cost of the biocatalyst continues to be a barrier to current enzymatic procedures, although advancements have recently been achieved, enabling the first synthetic enzymatic biodiesel synthesis. The fabrication of biodiesel which is enzymatic is primarily desirable due to the initial materials (waste frying oils, oils that were having high water content, etc.), where standard interesterification which is chemical is seldom applicable.
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Taber, Douglass F. "The Fuwa Synthesis of Didemnaketal B." In Organic Synthesis. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190646165.003.0097.
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Didemnaketal B 3 may be an artifact of isolation, derived from didemnaketal C, in which one of the methyl esters is instead an ethylsulfonate. Nevertheless, it is B, not C, that is a potent inhibitor of HIV protease. Haruhiko Fuwa of Tohoku University has provided (Chem. Eur. J. 2014, 20, 1848) a detailed account of the synthesis of 3, including the necessary revision of the absolute configuration of seven of the stereogenic centers. A central feature of the modular synthesis of 3 was the cyclization of 1 to the thermodynamically most favorable diastereomer of the spiroketal 2. Three components were combined for the synthesis of 3. The upper sidechain was prepared from commercial citronellal 4. Reduction followed by protection and ozonolysis delivered the aldehyde 5, that was carried on to the alkyne 6. Hydroiodination using the method previously reported by the authors (OHL May 30, 2011) gave 7, that was oxidized to 8 and then to the ester 9. Lactone formation by ring-closing metathesis is difficult because of the substantial preference for the extended conformation of the ester. As illustrated by the conversion of 10 to 11, this can be overcome by complexation with a Lewis acid. Conjugate addition followed by phosphorylation completed the preparation of the enol phosphate 12. The third component of 3 was the lactone 15, prepared by deprotonation/kinetic protonation with 14 of 13. This was carried on to the sulfone 16, that was coupled with 17. Although the Julia–Kocienski reaction usually strongly favors the E alkene, in this case it was necessary to optimize both the base and the solvent. Sharpless asymmetric dihydroxylation followed by coupling with the enol phosphate 12 then completed the preparation of the diol 1. Addition of the ketene silyl acetal 18 to the aldehyde derived from 2 proceeded to give the undesired diastereomer 19. This was overcome by oxidation to the ketone followed by enantioselective reduction. The iodide 9 was added to the aldehyde 20 to give a 1.8:1 mixture of diastereomers, the major one of which was didemnaketal B 3. This full paper is worth reading in detail. The work reported underlines the importance of powerful protocols for carbon–carbon bond formation that maintain high diastereocontrol in stereochemically complex environments.
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Taber, Douglass F. "The Gin Synthesis of Neofinaconitine." In Organic Synthesis. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190646165.003.0087.
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The hexacyclic norditerpenoid alkaloids, including neofinaconitine 4, isolated from traditional Chinese and Japanese antiarrhythmics and analgesics, have long offered a challenge to organic synthesis. The late David Y. Gin of the Memorial Sloan-Kettering Cancer Center envisioned (J. Am. Chem. Soc. 2013, 135, 14313) an approach to 4 by way of the Diels–Alder coupling of 1 and 2. This project was completed under the supervision of his colleague Derek S. Tan. The cyclopropene 6 was prepared from the ester 5. Addition of 6 to the diene derived from 7 proceeded with modest regioselectivity to give, after enol ether hydrolysis, the ketone 8. After two-carbon extension of the ketone with 9 to the ester 10, ionization with HBr led to 11, that was carried on the diene 1. Opening of caprolactam 12 with ethylamine followed by oxidation delivered the aldehyde 13. Acid-mediated cyclization to the enamide followed by bromination gave 14. Carbomethoxylation followed by selenylation and oxidation completed the preparation of the dienophile 2. With the sterically-demanding Br blocking one face of the diene, Diels–Alder cycloaddition of 2 to 1 proceeded with high diastereocontrol, leading after hydrolysis of the intermediate silyl enol ether to the ketone 15. Oxidative cleavage of the more accessible alkene followed by elimination led to the ketone 16, that on exposure to acid underwent Mannich cyclization. Oxidation followed by elimination completed the preparation of 17. Reductive cyclization to 18 established the sixth and last ring of 4, but the tertiary alcohol was lacking. This was installed by selenylation followed by oxidation, presumably by way of the transient anti-Bredt enone. There are two classes of the norditerpenoid alkaloids, having 18 and 19 carbons respectively. The ester 19 could be a versatile precursor to both classes. For 4, the carbon had to be removed. Reduction and protection followed by oxidative cleavage gave 20, that was carried on to neofinaconitine 4.
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Taber, Douglass F. "The Hoveyda Synthesis of Disorazole C1." In Organic Synthesis. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190646165.003.0102.
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Disorazole C1 3, isolated from fermentation of the myxobacterium Sorangium cellulosum, shows antifungal and anticancer activity. Amir H. Hoveyda of Boston College applied (J. Am. Chem. Soc. 2014, 136, 16136) recent advances in alkene metathesis from his group to enable the efficient assembly of 2 and so of 3. The ester 1 was assembled from the alcohol 11 and the acid 18. The preparation of 11 began with the enantioselective addition of 5 to 4 to give 6 and then 7, as described by Kalesse (Angew. Chem. Int. Ed. 2010, 49, 1619). Leighton allylation led to 8, that was then coupled with 9 to give 10 with high Z selectivity. Iodination of 10 followed by deprotection then completed the assembly of 11. The starting material for the acid 18 was the allylic alcohol 13. As reported by Cramer (Angew. Chem. Int. Ed. 2008, 47, 6483), exposure of the racemic alcohol 12 to vinyl acetate in the presence of Amano lipase PS converted one enantiomer to the acetate, leaving 13. Methylation of the secondary alcohol followed by acid-mediated removal of the t-butyl ester led to the acid 14, that was converted to the corresponding acyl fluoride and coupled with serine Me ester 15 to give 16. After cyclization to the oxazole 17, cross metathesis with five equivalents of 4-bromo-1-butene gave the homoallylic bromide, that was readily eliminated with DBU to give, after saponification, the acid 18. The cross metathesis of the coupled ester 1, a polyene, with 9 proceeded with remarkable selectivity to give 2, again as the Z geometric isomer. On exposure to the Heck catalyst Pd [(o-tolyl)3P]2, 2 dimerized efficiently. The deprotection was not straightforward, but conditions (H2SiF6, CH3OH, 4°C, 72 h) were found that delivered 3 in 68% yield.
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Taber, Douglass. "The Paquette Synthesis of Fomannosin." In Organic Synthesis. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199764549.003.0096.
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The compact sesquiterpene ( + )-fomannosin 3, isolated from the pathogenic fungus Fomes annonsus, presents an interesting set of challenges for the organic synthesis chemist, ranging from the strained cyclobutene to the easily epimerized cyclopentanone. In the synthesis of 3 developed (J. Org. Chem . 2008, 73, 4548) by Leo A. Paquette of Ohio State University, the cyclopentane was constructed by ring-closing metathesis of 1. The real challenge of the synthesis was the enantiospecific preparation of 1 from D-glucose. The starting point for the preparation of 1 was the glucose derivative 4. Selective acetonide hydrolysis followed by oxidative cleavage gave the ester 5, which on base treatment followed by hydrogenation delivered the endo ester 6. Condensation of the enolate of 6 with formaldehyde proceeded with high diastereoselectivity, to give, after protection, the ester 7. Conversion of the ester to the vinyl group, exposure to methanolic acid and ether formation completed the preparation of 9. The construction of the cyclobutane of 1 was effected by an interesting application of the Negishi reagent (Cp2ZrCl2/2 x BuLi). Complexation of Cp2Zr with the alkene followed by elimination generated an allylic organometallic 11, which added to the released aldehyde to give the cyclobutanes 12 and 13 in a 2.4:1 diastereomeric ratio. Homologation of the aldehyde 13 and subsequent oxidation were straightforward, but subsequent methylenation of the hindered carbonyl was not. At last, it was found that Peterson olefination worked well. Metathesis then delivered the cyclopentene 2. The last carbons of the skeleton were added by intramolecular aldol cyclization of the thioester 16. The seemingly simple task of converting the alkene of 17 into a ketone proved challenging. Eventually, dihydroxylation followed by oxidation, and then SmI2 reduction, completed the transformation. This still left the challenge of controlling the cyclopentane stereogenic center. Remarkably, dehydration and epimerization led to (+)-Fomannosin 3 as a single dominant diastereomer.
Conference papers on the topic "Wax ester synthesis"
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Gu, Ji-Dong, and Yingying Wang. "Degradation of the Plasticizers Orthd-Dimethyl Phthalate Ester by Environmental Bacteria." In CORROSION 2004. NACE International, 2004. https://doi.org/10.5006/c2004-04586.
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Abstract Synthetic organic compounds in polymeric materials can migrate out to the environment and disrupt the endocrine system in organisms, including humans. These compounds can also promote the growth of microorganisms on surfaces of materials. They have been detected in a wide range of environments and their concentration can be as high as 10 g L-1 of phthalic acid and dimethyl phthalate ester (DMPE) in landfill leachate. We initiated an investigation on biodegradability of phthalic acid and DMPE’s. Enrichment cultures of bacteria obtained from activated sludge and mangrove can fully mineralize this group of compounds within a short period of time. However, it was also found that single species of bacteria were not capable of completely degrading DMPE’s and consortia of two or three pure species could mineralize DMPE’s at an initial concentration of 400 m g L-1 within one week. Two selective systems consisting of bacteria isolated from activated sludge and mangrove are discussed here. Degradation intermediates were isolated and identified, and the degradation pathway has been established. It is apparent that environmental hormones DMPE’s could be mineralized by natural microorganisms in proper association.
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Obeyesekere, Nihal, Ali Naraghi, and John S. McMurray. "Synthesis and Evaluation of Biopolymers as Low Toxicity Corrosion Inhibitors for North Sea Oil Fields." In CORROSION 2001. NACE International, 2001. https://doi.org/10.5006/c2001-01049.
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Abstract The paper describes the synthesis and evaluation of a series of environmentally friendly corrosion inhibitors. These products were designed especially to use in North Sea Oil fields and in other environmentally sensitive areas as green inhibitors of CO2 corrosion. More than thirty peptides, some with random amino acid sequences and some ordered copolymers were synthesized by solid phase peptide techniques using the Fmoc/tert-butyl protection strategy. In these syntheses the C-terminal residue was coupled to a resin and peptides were built out either by adding various Fmoc-Xxx-Yyy-Zzz units or by sequential addition of Fmoc-amio acids. The tri-peptide segments were synthesized in an aqueous solution by the successive addition of three N-hydroxysuccinimide esters of amino acids. In sequential addition, a single activated amino acid was added one at a time to the growing peptide on the solid support until the desired length was reached. The peptides were screened as corrosion inhibitors by exposure test. The promising candidates were again screened by RCE tests for performance. A few biopolymers were selected which were then subjected to a battery of tests as water-soluble green chemicals. Finally, two biopolymers were selected with low toxicity, moderate corrosion protection, high biodegradability, and low bioaccumulation
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Lake, R. D., R. B. Henrich, W. H. Julius, and T. S. McQuarrie. "Evaluation of Corrosion Resistant Resins for Hot/Wet Chlorine Service." In CORROSION 1986. NACE International, 1986. https://doi.org/10.5006/c1986-86281.
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Abstract A study was undertaken to compare the resistance of several kinds of commercially produced polyester and vinyl ester resins to hot, wet chlorine gas. The study includes corrosion grade polyester resins of the bisphenol A type, modified-bisphenol A, brominated-bisphenol A, modified, brominated bisphenol A and chlorendic type. Vinyl esters under investigation comprise modified, brominated, and modified, brominated bisphenol A epoxy derived resins as well as an epoxy-novolac type. Final, twelve month exposure data is presented for several resins in conventional "C" glass veil/"E" glass mat laminate constructions. Interim results are reported for a larger number of resins after six months of the planned twelve month exposure period. Among these are examples of laminates in which "A" glass veil is substituted for "C" glass veil or both veil and mat are of the "A" glass type. Data is also given for a laminate of standard construction with a synthetic veil and another with polyester fiber reinforcement used throughout.
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Popescu, Mihaela Alexandra, Elena-Emilia Sirbu, Catalina Calin, Cristina Popa, and Cristina Emanuela Enascuta. "PHOSPHATE REMOVAL ON BIOCHAR." In 24th SGEM International Multidisciplinary Scientific GeoConference 24. STEF92 Technology, 2024. https://doi.org/10.5593/sgem2024/4.1/s17.22.
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Biochar can be used as an alternative and efficient adsorbent for organic and inorganic pollutants. Therefore, based on previous study in which, a biochar loaded with mixed metal oxides of iron, tin or titanium catalysts results as a by-product of levulinic esters synthesis from biomass carbohydrates, this paper aim was to test this residue as biochar for the retention of phosphate from water samples. The obtained adsorbents based on Fe2O3-SnO2 and Fe2O3-La2O3-TiO2 were characterized by FT-IR and TGA analyses. The effects of adsorbent dosage, initial concentrations of phosphate, and adsorption time were investigated. The results showed that each synthetized adsorbent was able to remove phosphate from aqueous samples with efficiency above 80%. The experimental data obtained were used to estimate the equilibrium adsorption capacity for the two adsorbents applying three machine learning methods. The results obtained were in good agreement with the experimental data indicating that Support Vector Machine has a good potential in the prediction of B-Fe2O3-SnO2 and artificial neural network model is the best for Fe2O3-La2O3-TiO2 to predict adsorption capacity..
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Liu, Ya, Haiping Lu, and Rebecca Vilain. "Investigation of Scale Inhibitor Interference on Sulfate Measurement and Method to Remove the Interference." In CONFERENCE 2022. AMPP, 2022. https://doi.org/10.5006/c2022-17595.
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Abstract The sulfate level in the effluent of sulfate removal unit (SRU) is usually continuously monitored for quality assessment. SulfaVer 4 method of Hach Company is a commonly used technique for sulfate measurement, and it is based on turbidity measurement caused by barite formation. The residual scale inhibitors in the effluent of SRU were observed to interfere sulfate measurement by inhibiting barite formation. Twelve different types of scale inhibitors were investigated on their impact on sulfate measurement. It was found that phosphonate, phosphate ester, and certain poly-carboxylate scale inhibitors do not interfere sulfate measurement, but sulfonate co-polymer and phosphino-polycarboxylate scale inhibitors showed strong interferences, i.e., the measured sulfate levels were lower than the actual concentrations. Several pre-treatments for the test sample were attempted to remove the interference. One pre-treatment method, called “Fe2+ thermal aging”, was found to completely removed scale inhibitor interference on sulfate measurements without causing any side effect. The method has been verified with both synthetic brine and field brine. This pre-treatment method can also help improving the accuracy of residual scale inhibitor analysis.
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Dolmat, Norfadilah, Azmi Mohammed Nor, Mohd Shamsul Farid Samsudin, Russel Varley, and Jane Zhang. "Autonomous Healing of Smart Coating Materials for Corrosion Protection of Oil and Gas Assets." In CONFERENCE 2024. AMPP, 2024. https://doi.org/10.5006/c2024-20901.
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Abstract Most assets in the oil and gas sector that use metal substrates e.g., pipe supports, or structures are susceptible to corrosion problems primarily because of continual exposure of damaged areas to severe environmental conditions. The proliferation and merging of corrosion issues can cause catastrophic failure of materials, resulting in a reduction in the service life of the materials. To avoid these issues, it is crucial to protect the scratch or minor crack area as quickly as possible so that it does not spread too far. In this case, self-healing as a smart material can be applied to the coating system to repair coating damage instantaneously. Self-healing works in multiple functions where it can be used to protect against corrosion and at the same time heal the damaged area itself. In this research, the experimental work includes boronic ester (BE) and polyurethane (PU) synthesis, BE-PU coating specimen preparation, characterization and performance analysis. BE was introduced in the polyurethane (PU) and applied as an additional coating layer to the existing coating system according to PETRONAS technical standard (PTS) requirement with a thickness of approximately 300-400 μm. The healing performance of the scribed coating at room and 60°C with 80% humidity level was initially evaluated using 3D profilometer microscopy and electrical impedance spectroscopy (EIS). Corrosion resistance performance was evaluated by performing long term 3000 hours salt spray and 4200 hours cyclic UV. The mechanical performance or compatibility of the self-healing with current coating system was also assessed using a pull-off adhesion test and abrasion test. The assessment of the scratched BE-PU self-healing using 3D profilometer microscopy demonstrated remarkable healing efficiency of more than 85% and has excellent corrosion resistance performance through salt spray and cyclic UV test. In addition, BE-PU self-healing showed significant adhesion efficiency with more than 300 psi and abrasion performance.
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Gonawan, Fadzil Noor, and Azlina Harun Kamaruddin. "Conceptual study of enzyme-catalyzed synthesis of wax ester via mathematical modeling application." In ADVANCES IN FRACTURE AND DAMAGE MECHANICS XX. AIP Publishing, 2023. http://dx.doi.org/10.1063/5.0147980.
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LIMA, L. C. D., D. G. C. PERES, N. S. OKURA, and A. A. MENDES. "WAX ESTER SYNTHESIS CATALYZED BY A HOMEMADE HETEROGENEOUS BIOCATALYST AND ITS PHYSICOCHEMICAL CHARACTERIZATION." In XXII Congresso Brasileiro de Engenharia Química. Editora Blucher, 2018. http://dx.doi.org/10.5151/cobeq2018-pt.0925.
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Wakabayashi, Toshiaki, Yasuo Kishida, Akira Tsukuda, Toshifumi Atsuta, and Satoshi Suda. "Tribology and Cutting Performance of Esters as a MQL Machining Lubricant." In ASME/STLE 2007 International Joint Tribology Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/ijtc2007-44247.
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Synthetic esters have recently been used as a high performance lubricant in minimal quantity lubrication (MQL) machining. However, there is little understanding about the relationship between the cutting performance and the tribological action of these esters. This study therefore investigates the tribological characteristics of some synthetic polyol esters for MQL machining by using a basic friction test. In the results of this friction test, an ester having more ester bonds in one molecule showed the better lubricity and such trend was prominent at higher sliding speed in the range of the test conditions. The study also evaluated the practical cutting performance of these polyol esters by using a turning test. This evaluation presented, particularly at the cutting speed of 50m/min, an ester showing the better lubricity provided the higher cutting performance.
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Davison, Evan, Jessica Otto, Sandeep Kumar, and Randy Maglinao. "Production of Branched Esters via Continuous Alkylation of Fatty Acid Methyl Esters over Montmorillonite and h-zsm5 Catalysts." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/ezak5028.
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Abstract: Lignocellulosic and waste from the food industry offers a sustainable way to produce alternative transportation fuel and provide fiber and biomaterial. Thermochemical processes can depolymerize lignin into its phenolic monomers which can be upgraded to aromatic hydrocarbons. Fatty acids from food wastes have functional groups to accommodate selective synthesis of chemicals. These characteristics could be utilized as sustainable high-value additive products for fuels and lubricating oils. In the present study, an effective lubricity additive was synthesized via continuous alkylation of fatty acid methyl esters with aromatic hydrocarbons. A continuous fixed-bed reactor operated at atmospheric pressures was used. Acid-treated montmorillonite and H-ZSM5 were used as catalysts. The effects of the various catalysts on the liquid product composition were investigated while keeping other reaction conditions constant. An improved catalytic activity was achieved in montmorillonite catalyst compared to H-ZSM5 catalysts. The alkylation of fatty acid methyl esters with aromatic hydrocarbons over montmorillonite and alumina-supported Ni catalysts occurred at 200-210 °C.