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991.
Biofouling of sensors is a common problem when measuring biological samples. The adherence of proteins and biomolecules, called hemostasis, is the first of four steps that lead to biofouling and eventually a foreign body response. This typically occurs within the first hours after the exposure of the biosensor to a biological sample. The purpose of this study was to assess the effect of this initial step of biofouling on cyclic voltammetry and potentiometric measurements. The results show that biofouling occurred rapidly within minutes and strongly affected cyclic voltammetry measurements, while potentiometric measurements were minimally affected even after 24 hours. 相似文献
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We have used the single‐pulse shock tube technique with postshock GC/MS product analysis to investigate the mechanism and kinetics of the unimolecular decomposition of isopropanol, a potential biofuel, and of its reaction with H atoms at 918‐1212 K and 183‐484 kPa. Experiments employed dilute mixtures in argon of isopropanol, a radical scavenger, and, for H‐atom studies, two different thermal precursors of H. Without an added H source, isopropanol decomposes in our studies predominantly by molecular dehydration. Added H atoms significantly augment decomposition, mainly by abstraction of the tertiary and primary hydrogens, reactions that, respectively, lead to acetone and propene as stable organic products. Traces of acetaldehyde were observed in some experiments above ≈ 1100 K and establish branching limits for minor decomposition pathways. To quantitatively account for secondary chemistry and optimize rate constants of interest, we employed the method of uncertainty minimization using polynomial chaos expansions (MUM‐PCE) to carry out a unified analysis of all datasets using a chemical model–based originally on JetSurF 2.0. We find: k(isopropanol → propene + H2O) = 10(13.87 ± 0.69) exp(?(33 099 ± 979) K/ T) s?1 at 979‐1212 K and 286‐484 kPa, with a factor of two uncertainty (2σ), including systematic errors. For H atom reactions, optimization yields: k(H + isopropanol → H2 + p‐C3H6OH) = 10(6.25 ± 0.42) T2.54 exp(?(3993 ± 1028) K /T) cm3 mol?1 s?1 and k(H + isopropanol → H2 + t‐C3H6OH) = 10(5.83 ± 0.37) T2.40 exp(?(1507 ± 957) K /T) cm3 mol?1 s?1 at 918‐1142 K and 183‐323 kPa. We compare our measured rate constants with estimates used in current combustion models and discuss how hydrocarbon functionalization with an OH group affects H abstraction rates. 相似文献
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Cabrera Pérez Laura C. Padilla-Martínez Itzia I. Cruz Alejandro Correa Basurto José Miliar García Ángel Hernández Zavala Argelia A. Gómez López Modesto Rosales Hernández Martha C. 《Molecular diversity》2020,24(4):1-14
Molecular Diversity - 11-Beta hydroxysteroid dehydrogenase type 1 (11β-HSD1) regulates cortisol levels mainly in adipose, hepatic and brain tissues. There is a relationship between the high... 相似文献
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Laura J. Parry Victoria Vinader Ian J. Scowen Vipul K. Patel Kamyar Afarinkia 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):195-199
Abstract The Horner-Wittig reaction between diphenyl(2-phenylpropyl)phosphine oxide and 1-naphtaldehyde affords an equal mixture of the cis and trans isomers even though the formation of the initial adduct is selective. 相似文献