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The European Physical Journal C - New physics frameworks like the next-to-minimal supersymmetric standard Model and the Next-to-2-Higgs-doublet Model contain three neutral CP-even Higgs bosons. It... 相似文献
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Halil pek Jale Hacalolu 《Journal of polymer science. Part A, Polymer chemistry》2019,57(15):1711-1716
In this work, 3‐amino phenyl boronic acid (AB) was used as an aniline derivative in the preparation of polybenzoxazine based on phenol. In order to investigate the effect of boronic acid on thermal characteristics, polybenzoxazines based on pure aniline and 50% aniline and AB mixture were also prepared and analyzed. Significant improvements in thermal characteristics, increase in thermal stability and char yield, was recorded for the polymers based on AB or its mixture. This behavior was associated with crosslinked structures generated by condensation reactions of B? OH groups. Morphologic and thermal characteristics of polybenzoxazines samples were investigated by NMR, FTIR, DSC, TGA, and direct pyrolysis mass spectrometry (DP‐MS) techniques. Application of DP‐MS technique also supplied additional information on crosslinked structures produced by boronic acid units. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1711–1716 相似文献
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Kimberly B. Shepard Halil Gevgilili Miguel Ocampo Jia Li Frank T. Fisher Dilhan M. Kalyon 《Journal of Polymer Science.Polymer Physics》2012,50(21):1504-1514
There is significant potential in improving the mechanical, electrical, and thermal properties of engineering plastics, including poly(ether imide) (PEI), with various nanoinclusions such as multiwalled carbon nanotubes (MWCNTs). However, this potential can only be fully realized through a thorough understanding of the rheological behavior and the thermomechanical histories that the nanocomposites are exposed to during their preparation and the resulting effective properties. In this study, nanocomposites of PEI and MWCNTs were prepared using a solution processing method under different dispersion conditions, and the viscoelastic material functions of the nanocomposites were characterized as functions of concentration of CNTs in the 1–5% by weight range (volume fraction, ? = 0.006–0.03) and temperature. The storage modulus and magnitude of complex viscosity values of the PEI nanosuspensions increased by as much as 3500% and 800%, respectively, at ? = 0.03, along with similar orders of magnitude increases observed or predicted in other viscoelastic material functions. Such increases reflect how nanotube incorporation and network formation can drastically alter the flow and deformation behavior of the PEI/CNT nanosuspensions at processing‐relevant temperatures and deformation rates. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献
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Bayraktar H Ghosh PS Rotello VM Knapp MJ 《Chemical communications (Cambridge, England)》2006,(13):1390-1392
Functionalized gold nanoparticles bind selectively to cytochrome c or cytochrome c peroxidase and inhibit enzyme turnover. 相似文献
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We consider geometric process (GP) when the distribution of the first occurrence time of an event is assumed to be Weibull. Explicit estimators of the parameters in GP are derived by using the method of modified maximum likelihood (MML) proposed by Tiku [24]. Asymptotic distributions and consistency properties of these estimators are obtained. We show that our estimators are more efficient than the widely used modified moment (MM) estimators via Monte Carlo simulation study. Further, two real life examples are given at the end of the paper. 相似文献
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