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Fe 4 (OAc) 10 [EMIM] 2 : Novel Iron-Based Acetate EMIM Ionic Compound
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Investigation into the Decomposition Pathways of an Acetal-Based Plasticizer
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Metabolic Engineering of E. coli for Enhanced Diols Production from Acetate
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Two-dimensional copper nanosheets for electrochemical reduction of carbon monoxide to acetate
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Selective CO-to-acetate electroreduction via intermediate adsorption tuning on ordered Cu?Pd sites
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Formic and acetic acid p K a values increase under nanoconfinement
The dissociation constants of organic acids decrease (p K a values increase) when they are confined within silica nanopores filled with aqueous solutions. Nanoconfinement stabilizes the protonated species.
Vitrimerization of crosslinked poly(ethylene-vinyl acetate): the effect of catalysts
DFT calculations and experiments with four zinc salts as transesterification catalysts show discrepancies between computational and experimental flow activation energies, highlighting the importance of catalyst thermal stability and molecular size.
Toward a glycyl radical enzyme containing synthetic bacterial microcompartment to produce pyruvate from formate and acetate
Formate has great potential to function as a feedstock for biorefineries because it can be sustainably produced by a variety of processes that don’t compete with agricultural production. However, naturally formatotrophic organisms are unsuitable for large-scale cultivation, difficult to engineer, or have inefficient native formate assimilation pathways. Thus, metabolic engineering needs to be developed for model industrial organisms to enable efficient formatotrophic growth. Here, we build a prototype synthetic formate utilizing bacterial microcompartment (sFUT) encapsulating the oxygen-sensitive glycyl radical enzyme pyruvate formate lyase and a phosphate acyltransferase to convert formate and acetyl-phosphate into the central biosynthetic intermediate pyruvate. This metabolic module offers a defined environment with a private cofactor coenzyme A that can cycle efficiently between the encapsulated enzymes. To facilitate initial design-build-test-refine cycles to construct an active metabolic core, we used a “wiffleball” architecture, defined as an icosahedral bacterial microcompartment (BMC) shell with unoccupied pentameric vertices to freely permit substrate and product exchange. The resulting sFUT prototype wiffleball is an active multi enzyme synthetic BMC functioning as platform technology.
Zymomonas mobilis ZM4 Utilizes an NADP + -Dependent Acetaldehyde Dehydrogenase To Produce Acetate
Biofuel production from nonfood crops is an important strategy for reducing carbon emissions from the transportation industry, but it has not yet become commercially viable. An important avenue to improve biofuel production is to enhance the characteristics of fermentation organisms by decreasing by-product formation via genetic engineering.
Cell wall O-acetyl and methyl esterification patterns of leaves reflected in atmospheric emission signatures of acetic acid and methanol
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Engineered production of lactate and acetate short-chain esters in Escherichia coli.
Abstract not provided.
Sustainable Conversion of Carbon Dioxide and Shale Gas to Green Acetic Acid via a Thermochemical Cyclic Redox Scheme (Final Report)
The large-scale production of commodity chemicals relies heavily on the combustion of fossil fuels. As a result, enormous amounts of carbon dioxide (CO 2 ) are emitted which severely affects the global climate. The challenges for CO 2 utilization reside in the high stability of CO 2 molecules relative to the products, which requires the addition of significant external energy and overcoming slow and/or unfavorable reaction kinetics/thermodynamics. Chemical looping dry reforming of methane (CLDRM), also known as a hybrid redox process (HRP), is a promising alternative that allows the utilization of CO 2 and domestic shale gas resources to produce commodity chemicals. HRP works in two steps: In the first step, a redox catalyst reacts with methane to yield synthesis gas with a H 2 /CO ratio near 2:1, which is suitable for methanol and Fischer–Tropsch synthesis. The reduced redox catalyst then reacts with an oxidizing agent, such as CO 2 , to yield CO. In comparison to conventional thermochemical CO 2 splitting approaches, the use of methane as the reducing agent in HRP can significantly lower the operating temperature for CO 2 splitting.
Ultrasonic Characterization of Ethylene Vinyl Acetate (EVA) Crosslinking for Quality Assurance and Lamination Process Control (US-Xlink)
Module makers strive to cut lamination processing times to enhance production throughput and reduce costs. If overdone, this might lead to poor EVA quality due to incomplete EVA crosslinking and a large concentration of potentially harmful reactants. Those deficiencies are frequently missed during production quality testing as initially their impact on power output is small. Additionally, the crosslinking agent is frequently inhomogeneously dispersed across the EVA foils such that local destructive characterization procedures such as differential scanning calorimetry (DSC), Soxhlet extraction, swelling methods, or mechanical tests provide only a limited amount of information. However, these defects and inhomogeneities can become considerably more important during field operation, dramatically reducing long-term power yield, and increasing LCOE. Examples of typical long-term module degradation modes relating to poor lamination process conditions include cell breakage, corrosion of the metallization, delamination, and local quality deficiencies. To provide reliable material characterization in a manufacturing setting, we devised a non-destructive technology that uses ultrasound to evaluate the quality of interface adhesion and the degree of crosslinking. As a calibration reference, DSC measurements were employed. Although the potential of ultrasonic approaches for this purpose has already been noted, those previous methods were generally limited to local qualitative measurements. Furthermore, variations in EVA thickness and temperature had a substantial impact on them. The solution we propose solves these limitations by employing ultrasonic absorption rather than relying solely on sound velocity data.