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Claudia V. Lopez Menisha S. Karunarathna Moira K. Lauer Charini P. Maladeniya Timmy Thiounn Edward D. Ackley Rhett C. Smith 《Journal of polymer science. Part A, Polymer chemistry》2020,58(16):2259-2266
Here are reported composites made by crosslinking unsaturated units in canola, sunflower, or linseed oil with sulfur to yield CanS , SunS , and LinS , respectively. These plant oils were selected because the average number of crosslinkable unsaturated units per triglyceride vary from 1.3 for canola to 1.5 for sunflower and 1.8 for linseed oil. The remeltable composites show compressive strengths that increase with increasing unsaturation number from CanS (9.3 MPa) to SunS (17.9 MPa) to LinS (22.9 MPa). These values for SunS and LinS are competitive when compared with the value of 17 MPa required for residential building using traditional Portland cement. The plant oil composites are recyclable over many cycles and can retain up to 100% of strength after 24 hr in oxidizing acid under conditions where Portland cement is dissolved in under 30 min. Infusion of the composites into premade cement blocks affords them with significantly improved acid resistance as well. This work thus provides a simple, nearly 100% atom economical route to convert plant oils and waste sulfur to composites having enhanced performance over commercial structural materials. 相似文献
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Dr. Sarah Lopez Dr. Caroline Marchi-Delapierre Dr. Christine Cavazza Dr. Stéphane Ménage 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(70):16633-16638
Performing a heterogeneous catalysis with proteins is still a challenge. Herein, we demonstrate the importance of cross-linked crystals for sulfoxide oxidation by an artificial enzyme. The biohybrid consists of the insertion of an iron complex into a NikA protein crystal. The heterogeneous catalysts displays a better efficiency-with higher reaction kinetics, a better stability and expand the substrate scope compared to its solution counterpart. Designing crystalline artificial enzymes represents a good alternative to soluble or supported enzymes for the future of synthetic biology. 相似文献
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Y. Kudriavtsev A. Hernandez R. Asomoza S. Gallardo M. Lopez K. Moiseev 《Surface and interface analysis : SIA》2017,49(2):145-148
We have performed secondary ion mass spectrometry depth profiling analysis of III–V based hetero‐structures at different target temperatures and found that both the surface segregation and surface roughness caused by ion sputtering can be radically reduced if the sample temperature is lowered to ?150 °C. The depth profiling of ‘frozen’ samples can be a good alternative to sample rotation and oxygen flooding used for ultra‐low‐energy depth profiling of compound semiconductors. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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The linear stability of the flow between concentric cylinders, with the inner cylinder rotating at a constant angular velocity
and the outer cylinder with an angular velocity varying harmonically about a zero mean, is addressed. The bifurcations of
the base state are analyzed using Floquet theory, paying particular attention to non-axisymmetric bifurcations which are dominant
in significant regions of parameter space. In these regions the spiral modes of the unforced system become parametrically
excited and dominant. This is typical behavior of parametrically forced extended systems, where some modes are stabilized,
but others are simultaneously excited. The flow structure of the bifurcated states are examined in detail, paying particular
attention to the dynamic implications of their symmetries, and in particular how and when subsequent period doublings are
inhibited.
Received 5 November 2001 and accepted 29 March 2002 Published online: 2 October 2002
RID="*"
ID="*" This work was supported by NSF Grants INT-9732637 and CTS-9908599 (U.S.A.) and MCYT Grants PB97-0685 and BFM2001-2350
(Spain).
Communicated by H.J.S. Fernando 相似文献
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Braulio Aranda Sergio A. Moya Andres Vega Gonzalo Valdebenito Sofia Ramirez‐Lopez Pedro Aguirre 《应用有机金属化学》2019,33(4)
Aminocarbonylation of aryl halides, homogeneously catalysed by palladium, is an efficient method that can be employed for obtaining amides for pharmaceutical and synthetic applications. In this work, palladium (II) complexes containing P^N ligands were studied as catalysts in the aminocarbonylation of iodobenzene in the presence of diethylamine. Two types of systems were used: a palladium (II) complex formed in situ; and one prepared prior to the catalytic reaction. In general, the palladium complexes studied achieved high conversions in an average reaction time of less than 2 hr, which is less than that for the standard system (Pd (II)/PPh3) used. The pre‐synthesized complexes were faster than their in situ counterparts, as the latter require an induction time to form the Pd/P^N species. The structure and electronic properties of the ligand P^N can influence both the activity and the selectivity of the reaction, stabilizing the acyl‐palladium intermediates formed in a better manner. 相似文献
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A simple and rapid method for the preparation of a series of novel quinoxaline derivatives in the presence of Ag+ is reported. 相似文献
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Lopez Kenneth Pinheiro Silvana Zamora William J. 《Journal of computer-aided molecular design》2021,35(8):923-931
Journal of Computer-Aided Molecular Design - A multiple linear regression model called MLR-3 is used for predicting the experimental n-octanol/water partition coefficient (log PN) of 22... 相似文献