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181.
The total phenolic contents and the essential oil compositions of the previously unknown Stachys taxa (Labiatae), including Stachys pinardii Boiss, Stachys cretica L. subsp. mersinaea (Boiss.) Rech., and Stachys aleurites Boiss. & Heldr., all endemic to Turkey, were studied. Their essential oil compositions were investigated by GC-MS. It was
found that the main constituents were α-curcumene (34.10%) for S. cretica, cedrandiol (25.26%) and caryophyllene dioxide (22.15%) for S. pinardii, and (Z)-β-caryophyllene (31.60%) for S. aleurites. The total phenolic contents, by the Folin-Ciocalteu colorimetric method, of the S. pinardii, S. cretica subsp. mersinaea, and S. aleurites methanolic extract were found to be 600.74±0.23, 1200.94±0.11, and 900.61±0.06 mg gallic acid equivalent (GAE)/100 g in dried
herb, respectively.
Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 141–143, March–April, 2006. 相似文献
182.
Miller M Lee K Smith A Hansen J Bloch C van den Brand J Bulten H DeSchepper D Ent R Goodman C Jacobs W Jones C Korsch W Kramer L Leuschner M Lorenzon W Makins N Marchlenski D Meyer H Milner R Neal J Pancella P Pate S Pitts W von Przewoski B Rinckel T Savopulos G Sowinski J Sperisen F Sugarbaker E Tschalär C Unal O Welch T Zhou ZL 《Physical review letters》1995,74(4):502-505
183.
Lee K Miller MA Smith A Hansen J Bloch C van den Brand JF Bulten HJ Ent R Goodman CD Jacobs WW Jones CE Korsch W Leuschner M Lorenzon W Marchlenski D Meyer HO Milner RG Neal JS Pancella PV Pate SF Pitts WK von Przewoski B Rinckel T Sowinski J Sperisen F Sugarbaker E Tschalär C Unal O Zhou ZL 《Physical review letters》1993,70(6):738-741
184.
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186.
The dynamics of a simple model for an ocean wave energy converter is discussed. The model for the converter is a hybrid system
consisting of a pair of harmonically excited mass–spring–dashpot systems and a set of four state-dependent switching rules.
Of particular interest is the response of the model to a wide spectrum of harmonic excitations. Partially because of the piecewise-smooth
dynamics of the system, the response is far more interesting than the linear components of the model would suggest. As expected
with hybrid systems of this type, it is difficult to establish analytical results, and hence, with the assistance of an extensive
series of numerical integrations, an atlas of qualitative results on the limit cycles and other forms of bounded oscillations
exhibited by the system is presented. In addition, the presence of unstable limit cycles, the stabilization of the unforced
system using low-frequency excitation, the peculiar nature of the response of the system to high-frequency excitation, and
the implications of these results on the energy harvesting capabilities of the wave energy converter are discussed. 相似文献
187.
Journal of Solid State Electrochemistry - In this study, layer-by-layer assembled thin films composed of nickel hydroxide and graphene oxide nanosheets were produced via simple dip coating process.... 相似文献
188.
Dr. F. Eylul Sarac Oztuna Dr. M. Baris Yagci Prof. Ugur Unal 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(12):3131-3140
Composites of graphene (oxide) (GO) and first-row transition-metal cations (Co2+, Ni2+, Mn2+, Fe2+) are prepared by mixing GO and aqueous metal salt solutions. The amount of metal cation bound to GO nanosheets is calculated by using inductively coupled plasma mass spectrometry (ICP-MS) and the possible binding sites of the metals are investigated by means of attenuated total reflectance infrared (ATR-IR) spectroscopy and X-ray photoelectron spectroscopy (XPS) measurements. Electrodes loaded with the metal/GO composites are prepared by a simple drop-casting technique without any binders or conductive additives. The effect of electrochemical reduction on the structure of the composite electrodes is investigated by Raman spectroscopy, XPS, X-ray diffraction (XRD) analysis, and field emission scanning electron microscopy (FESEM). A detailed electrochemical characterization is performed for the utilization of the composite electrodes for electrochemical capacitors and possible oxygen reduction reaction electrocatalysts by cyclic voltammetry (CV) and rotating disk electrode measurements. The highest areal capacitance is achieved with the as-deposited Fe/GO composite (38.7 mF cm−2 at 20 mV s−1). In the cyclic stability measurements, rCo/GO, rNi/GO, rMn/GO, and rFe/GO exhibit a capacitance retention of 44, 1.1, 73, and 87 % after 3000 cycles of CV at 100 mV s−1, respectively. 相似文献
189.
Nonlinear Dynamics - We investigate the closed-loop control of a circular cylinder showing lock-in phenomena due to vortex-induced vibrations (VIV). The control action was implemented by a... 相似文献
190.
The purpose of the paper is to introduce Stancu‐type linear positive operators generated by Dunkl generalization of exponential function. We present approximation properties with the help of well‐known Korovkin‐type theorem and weighted Korovkin‐type theorem and also acquire the rate of convergence in terms of classical modulus of continuity, the class of Lipschitz functions, Peetre's K‐functional, and second‐order modulus of continuity by Dunkl analogue of Szász operators. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献