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51.
The choices of insect wing kinematic programs is not well understood,particularly the mechanism by which an insect selects a distortion to achieve flight control.A methodology to evaluate prospective kinematic control inputs is presented based on the reachable states when control actuation was constrained to a unit of power.The method implements a computationally-derived reduced order model of the insect’s flight dynamics combined with calculation of power requirement.Four kinematic inputs are evaluated based on this criterion for a Drosophila size insect in forward flight.Stroke bias is shown to be the dominant control input using this power normalized evaluation measure. 相似文献
52.
Crystal Blake Kimberly M Fabick Kenneth DR Setchell Trent D Lund Edwin D Lephart 《BMC neuroscience》2011,12(1):28
Background
Soy-derived isoflavones potentially protect against obesity and depression. In five different studies we examined the influence of soy-containing diets or equol injections on depression, serotonin levels, body weight gain (BW) and white adipose tissue (WAT) deposition in female Long-Evans rats at various stages of life [rats were intact, ovariectomized or experienced natural ovarian failure (NOF)]. 相似文献53.
We report on the characterisation of 16 protic ionic liquids (PILs) prepared by neutralisation of primary or tertiary amines with a range of simple carboxylic acids, or salicylic acid. The extent of proton transfer was greater for simple primary amine ILs compared to tertiary amines. For the latter case, proton transfer was increased by providing a better solvation environment for the ions through the addition of a hydroxyl group, either on the tertiary amine, or by formation of PIL/molecular solvent mixtures. The library of PILs was characterised by differential scanning calorimetry and a range of transport properties (i. e. viscosity, conductivity and diffusivity) were measured. Using the (fractional) Walden rule, the conductivity and viscosity results were analysed with respect to their deviation from ideal behaviour. The validity of the Walden plot for PILs containing ions of varying sizes was also verified for a number of samples by directly measuring self-diffusion coefficients using pulsed-field gradient spin-echo (PGSE) NMR. Ionicity was found to decrease as the alkyl chain length and degree of branching of both the cations and anions was increased. These results aim to develop a better understanding of the relationship between PIL properties and structure, to help design ILs with optimal properties for applications. 相似文献
54.
A two-component reduction of Dirac wavefunctions and operators is used to identify situations where Dirac and Schrödinger phenomenology differ significantly. In this two-component form pseudovector and pseudoscalar coupling operators differ in a fashion that reduces the pseudovector coupling strength in the nuclear medium. This reduction promises to improve agreement between theory and experiment for various nuclear direct reactions. 相似文献
55.
Tim J. Wooster Simmi Abrol Jeffrey M. Hey Douglas R. MacFarlane 《Journal of polymer science. Part A, Polymer chemistry》2005,43(21):5072-5082
Novel aliphatic‐bridged bis(acenaphthalene)s are synthesized and evaluated as potential precursors to high‐temperature reactive monomers. It was found that as the length of the aliphatic bridging unit increased, the thermal stability of bis(acenaphthalene) increased and melting point decreased. The use of an alternative route for the introduction of the reactive vinyl group resulted in a dramatic increase in monomer purity. The increase in monomer purity resulted in the creation of a processing window that enabled samples to be melt cast prior to polymerization, greatly improving their suitability as high‐temperature polymers. Polymerized samples were found to have high thermal stability, indicating they have potential as high temperature materials. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43:5072–5082, 2005 相似文献
56.
Clare BR Bayley PM Best AS Forsyth M MacFarlane DR 《Chemical communications (Cambridge, England)》2008,(23):2689-2691
Commonly used for purification, alumina and silica are found to contaminate ionic liquids with particles; these particles cannot be removed easily and can have a non-negligible impact on the electrochemical, spectroscopic and physical properties of an ionic liquid, including its nucleation and crystallisation kinetics. 相似文献
57.
Parolin TJ Salman Z Chakhalian J Song Q Chow KH Hossain MD Keeler TA Kiefl RF Kreitzman SR Levy CD Miller RI Morris GD Pearson MR Saadaoui H Wang D MacFarlane WA 《Physical review letters》2007,98(4):047601
The temperature dependence of the frequency shift and spin-lattice relaxation rate of isolated, nonmagnetic (8)Li impurities implanted in a nearly ferromagnetic host (Pd) are measured by means of beta-detected nuclear magnetic resonance (beta-NMR). The shift is negative, very large, and increases monotonically with decreasing T in proportion to the bulk susceptibility of Pd for T > T* approximately 100 K. Below T*, an additional shift occurs which we attribute to the response of Pd to the defect. The relaxation rate is much slower than expected for the large shift and is linear with T below T*, showing no sign of additional relaxation mechanisms associated with the defect. 相似文献
58.
Porous Nitrogen‐Doped Carbon Microspheres Derived from Microporous Polymeric Organic Frameworks for High Performance Electric Double‐Layer Capacitors
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Jinpeng Han Guiyin Xu Prof. Hui Dou Prof. Dr. Douglas R. MacFarlane 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(6):2310-2314
This research presents a simple and efficient method to synthesize porous nitrogen‐doped carbon microspheres (PNCM) by the carbonization of microporous poly(terephthalaldehyde‐pyrrole) organic frameworks (PtpOF). The common KOH activation process is used to tune the porous texture of the PNCM and produce an activated‐PNCM (A‐PNCM). The PNCM and A‐PNCM with specific surface area of 921 and 1303 m2 g?1, respectively, are demonstrated as promising candidates for EDLCs. At a current density of 0.5 A g?1, the specific capacitances of the PNCM and A‐PNCM are 248 and 282 F g?1, respectively. At the relatively high current density of 20 A g?1, the capacitance remaining is 95 and 154 F g?1, respectively. Capacity retention of the A‐PNCM is more than 92 % after 10 000 charge/discharge cycles at a current density of 2 A g?1. 相似文献
59.
Abraham TJ MacFarlane DR Pringle JM 《Chemical communications (Cambridge, England)》2011,47(22):6260-6262
Measurement of Seebeck coefficients in a range of ionic liquids (ILs) suggests that these electrolytes could enable the development of thermoelectric devices to generate electrical energy from low-grade heat in the 100-150 °C range. 相似文献
60.
We show that pharmaceutically active protic ionic liquids can be designed to rapidly transport through model membranes as neutral hydrogen bonded clusters. 相似文献