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51.
Hongkun He Saadyah Averick Elliot Roth David Luebke Hunaid Nulwala Krzysztof Matyjaszewski 《Polymer》2014
Covalent attachment of poly(ionic liquid)s (PILs) by click chemistry on glass or silicon (Si) surfaces was performed. Poly[1-(4-vinylbenzyl)-3-butylimidazolium bis(trifluoromethylsulfonyl)imide] (polyVBBI+Tf2N−), and copolymers of polyVBBI+Tf2N− with fluorescein O-methacrylate were synthesized by conducting an atom transfer radical polymerization (ATRP) from initiators containing azide or thioacetate groups. The azide- and thiol-terminated PILs were then successfully grafted onto alkyne and alkene modified glass/Si wafers by thermal azide–alkyne cycloaddition and photoinitiated thiol-ene click reactions, respectively. The modified surfaces were characterized by contact angle measurements and ellipsometry. The fluorescent PIL functionalized surfaces showed strong fluorescence under UV irradiation. This procedure of tethering PILs to substrates also provides an easy way to change the surface hydrophilicity by replacing the anions in the grafted PILs. The present approach could be readily applied for surface modifications with other types of PILs or their copolymers to achieve different functionalities on various surfaces. 相似文献
52.
Jerome Kluza Victoriane Peugnet Blanche Daunou William Laine Gwenola Kervoaze Gaëlle Rmy Anne Loyens Patrice Maboudou Quentin Fovez Corinne Grangette Isabelle Wolowczuk Philippe Gosset Guillaume Garon Philippe Marchetti Florence Pinet Muriel Pichavant Emilie Dubois-Deruy 《International journal of molecular sciences》2022,23(1)
Mitochondrial dysfunctions are implicated in several pathologies, such as metabolic, cardiovascular, respiratory, and neurological diseases, as well as in cancer and aging. These metabolic alterations are usually assessed in human or murine samples by mitochondrial respiratory chain enzymatic assays, by measuring the oxygen consumption of intact mitochondria isolated from tissues, or from cells obtained after physical or enzymatic disruption of the tissues. However, these methodologies do not maintain tissue multicellular organization and cell-cell interactions, known to influence mitochondrial metabolism. Here, we develop an optimal model to measure mitochondrial oxygen consumption in heart and lung tissue samples using the XF24 Extracellular Flux Analyzer (Seahorse) and discuss the advantages and limitations of this technological approach. Our results demonstrate that tissue organization, as well as mitochondrial ultrastructure and respiratory function, are preserved in heart and lung tissues freshly processed or after overnight conservation at 4 °C. Using this method, we confirmed the repeatedly reported obesity-associated mitochondrial dysfunction in the heart and extended it to the lungs. We set up and validated a new strategy to optimally assess mitochondrial function in murine tissues. As such, this method is of great potential interest for monitoring mitochondrial function in cohort samples. 相似文献
53.
Florence Bonnet-Magnaval Leïla Halidou Diallo Valrie Brunchault Nathalie Laugero Florent Morfoisse Florian David Emilie Roussel Manon Nougue Audrey Zamora Emmanuelle Marchaud Florence Tatin Anne-Catherine Prats Barbara Garmy-Susini Luc DesGroseillers Eric Lacazette 《International journal of molecular sciences》2022,23(1)
54.
Sylvain Lamoine Mlissa Cumenal David A. Barriere Vanessa Pereira Mathilde Fereyrolles Laëtitia Prival Julie Barbier Ludivine Boudieu Emilie Brasset Benjamin Bertin Yoan Renaud Elisabeth Miot-Noirault Marie-Ange Civiale David Balayssac Youssef Aissouni Alain Eschalier Jrme Busserolles 《International journal of molecular sciences》2022,23(1)
55.
In traditional microbial biobutanol production, the solvent must be recovered during fermentation process for a sufficient space-time yield. Thermal separation is not feasible due to the boiling point of n-butanol. As an integrated and selective solid-liquid separation alternative, solvent impregnated resins (SIRs) were applied. Two polymeric resins were evaluated and an extractant screening was conducted. Vacuum application with vapor collection in fixed-bed column as bioreactor bypass was successfully implemented as butanol desorption step. In course of further increasing process economics, fermentation with renewable lignocellulosic substrates was conducted using Clostridium acetobutylicum. Utilization of SIR was shown to be a potential strategy for solvent removal from fermentation broth, while application of a bypass column allows for product removal and recovery at once. 相似文献
56.
57.
Steven C. Cermak Jakob W. Bredsguard Robert O. Dunn Travis Thompson Kati A. Feken Katie L. Roth James A. Kenar Terry A. Isbell Rex E. Murray 《Journal of the American Oil Chemists' Society》2014,91(12):2101-2109
A series of 26 different antioxidants and commercial antioxidant packages designed for petroleum‐based materials, containing both natural and synthetic‐based materials, were evaluated with dimeric coconut‐oleic estolide 2‐ethylhexyl ester (2‐EH), a bio‐based material. The different antioxidants were categorized into different classes of phenolic, aminic, and blended/others materials. The oxidation onset temperatures (OT) using non‐isothermal pressurized differential scanning calorimetry (PDSC) were measured and recorded under previously reported standard conditions. The aminic series gave the best resistance to oxidation as defined by the PDSC method with OT of 246.6 and 244.7 °C for the best two performers, which was a 38 °C improvement over the uninhibited or unformulated dimer estolide material. The phenolic series, containing most of the naturally occurring antioxidants, was the least successful formulation package for the dimer estolide. The blended/other materials, which were specifically designed for petroleum‐based lubricants, did not have the best OT, since the estolides and other bio‐based materials interact differently than their petroleum counterparts. A number of potential antioxidants have been identified as useful additives for the estolides esters. The OT of the estolide and formulated materials correlated well with other bio‐based materials such as biodiesel. 相似文献
58.
Protonation and Solvation of Weak Organic Bases. IV. 1H-N.M.R. Spectroscopic Determination of the Basicity of Aliphatic Ketones From protonation ratios for a series of methyl and ethyl alkyl ketones 1—13 with gradually branched alkyl groups in the H2O–H2SO4 system, determined by 1H-n.m.r. spectroscopy, basicity and solvation parameters are systematically estimated by application of extrapolation procedures based on the Hammett acidity function H0 or the excess acidity X. 相似文献
59.
The physical process of jamming could take architectural sustainability/recyclability to a whole new level. It involves achieving structural rigidity through the crowding of particles within a confined space, rather than by permanent bonding. Project Z-Form, a collaboration between a team of physicists from the JaegerLab at the University of Chicago – including PhD students Kieran Murphy and Leah Roth and professor Heinrich Jaeger – and artist Dan Peterman , sets out to develop a pourable material that not only self-supports but can also bear loads. Here they explain the project and the concepts behind it. 相似文献
60.
In this study, the influence of pressure during processing on the refractive index (RI) of polycarbonate (PC) was investigated by transmission measurements on glass-filled samples with a spectrometer. In order to isolate the pressure dependence of the RI from other influencing parameters such as cooling rate, orientation and stress states, the samples were prepared in a pressure-specific volume-Temperature (pvT) instrument under constant cooling rate and temperature history and without shear effects. Subsequently, the RI was determined at the intersection of the dispersion curves of the glass and the polymer by evaluating the wavelength of the maximal transmission of the samples. The mean RI over the entire cross section of the sample is determined by the transmission measurements without complex sample preparation. The investigations show that the RI of PC increases by 3.26 E-6 per bar with increasing pressure. POLYM. ENG. SCI., 60:512–516, 2020. © 2019 The Authors. Polymer Engineering & Science published by Wiley Periodicals, Inc. on behalf of Society of Plastics Engineers. 相似文献