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141.
Rahmi Dumlupinar Faruk Demir Abdulhalik Karabulut Halil Karakurt 《Journal of Quantitative Spectroscopy & Radiative Transfer》2007,103(2):331-339
In this study, bean seedlings (Phaseolus vulgaris cv. Gina 2004) were exposed to chilling temperatures until leaves are wrinkled (9 day), that is, showed nyctinastic movement. Pulvinus were subsequently were cut from the leaves. Concentrations of inorganic elements (P, S, Cl, K, Ca, Cu) in the pulvinus were measured by wavelength-dispersive X-ray fluorescence (WDXRF) spectrometry. Results indicated that concentration change (%) was not significant for Ca (0.82) but it was significant for K, P, Cl, S, and especially Cu concentrations (5.4%, 12.8%, 40.2%, 43.7%, 365%, respectively) in pulvinus of plants exposed to chilling temperature compared with control group.We hypothesize here the presence of association between nyctinasti movement brought about by pulvinus at chilling temperature in bean and changes of K, P, Cl, S and especially Cu concentrations measured by WDXRF analysis method. 相似文献
142.
Periodica Mathematica Hungarica - In this paper, we first prove the existence and uniqueness of the solutions for a delayed hyperbolic partial differential equation by applying the progressive... 相似文献
143.
The nonlocal boundary value problem for a hyperbolic–elliptic equation in a Hilbert space is considered. The stability estimate for the solution of the given problem is obtained. The first and second orders of difference schemes approximately solving this boundary value problem are presented. The stability estimates for the solution of these difference schemes are established. The theoretical statements for the solution of these difference schemes are supported by the results of numerical experiments. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
144.
Faruk Civan 《Transport in Porous Media》2010,82(2):375-384
Gaseous flow regimes through tight porous media are described by rigorous application of a unified Hagen–Poiseuille-type equation.
Proper implementation is accomplished based on the realization of the preferential flow paths in porous media as a bundle
of tortuous capillary tubes. Improved formulations and methodology presented here are shown to provide accurate and meaningful
correlations of data considering the effect of the characteristic parameters of porous media including intrinsic permeability,
porosity, and tortuosity on the apparent gas permeability, rarefaction coefficient, and Klinkenberg gas slippage factor. 相似文献
145.
We investigate the optical characteristic,transverse magnetic(TM) and transverse electric(TE) band of twodimensional(2 D) square lattice photonic crystal structure,which is composed of cylindrical air regions positioned at the corners of the square shaped dielectric rods.We obtain the wide photonic bandwidths between TM1–TM2 and TM3–TM4 bands.According to the results,we demonstrate the band gaps close to each other in the TM and TE frequencies for proposed structures.The resulting photonic gaps are formed to be about 8% at the higher frequencies of TE modes(TE4–TE5)and TM modes(TM7–TM8 and TM9–TM10).In addition,we examine isotropically generated structures for light guiding properties and observe that the light is directed in a particular route without using any deflection.We also investigate the self-collimation effect with the designed structure.The obtained results reveal the influences of the radius of cylindrical air holes and the angle between these air holes on absolute and partial photonic band gaps.Moreover,we observe the TM and TE band gaps that overlap.It is thought that the obtained band overlap will provide an easy way to produce the photonic crystals in practical applications like photonic insensitive waveguide.It is also believed that these results can provide the photonic crystal structures to work as a beam deflecting and beam router in integrated optical circuit applications. 相似文献
146.
Faruk Temur 《Mathematische Zeitschrift》2013,273(3-4):1197-1214
We prove an ${L^2 \times L^2 \rightarrow L_t^qL_x^p }$ bilinear Fourier extension estimate for the cone when p, q are on the critical line ${1/q=(\frac{n+1}{2})(1-1/p)}$ . This extends previous results by Wolff, Tao and Lee-Vargas. 相似文献
147.
Orth ES Medeiros M Bortolotto T Terenzi H Kirby AJ Nome F 《The Journal of organic chemistry》2011,76(24):10345-10348
We report a detailed kinetic and mechanistic study of the reaction of a widely used therapeutic agent, deferoxamine (DFO), which contains three nucleophilic hydroxamate groups, with the model phosphate diester bis-2,4-dinitrophenylphosphate BDNPP. We clarify the mechanism by detecting important phosphorylated intermediates in the model reaction and show that the mechanism can be extended to the reaction with DNA. The effectiveness of DFO in cleaving DNA was examined over a range of pH in the absence and presence of a biologically available metal (Zn(2+)). The results inform and complement ongoing studies involving DFO, which can act as a powerful nucleophile toward DNA and other targets susceptible to nucleophilic attack. 相似文献
148.
Orth ES Wanderlind EH Medeiros M Oliveira PS Vaz BG Eberlin MN Kirby AJ Nome F 《The Journal of organic chemistry》2011,76(19):8003-8008
The phosphorylation of imidazole by two activated phosphate diesters and a triester gives phosphorylimidazole derivatives that are stable enough in aqueous solution to be observed and identified by ESI-MS/MS and NMR. Half-lives ranging from hours to days (in the case of the monoethyl ester) show that it is possible to design molecules with variable half-lives with potential to be used for biological intervention experiments as possible inhibitors of biosignaling processes or as haptens for the generation of antibodies. 相似文献
149.
Murat Faruk Us Usama Alshana Ibrahim Lubbad Nilgün G. Göğer Nusret Ertaş 《Electrophoresis》2013,34(6):854-861
Dispersive liquid–liquid microextraction based on solidification of floating organic drop (DLLME–SFO) was for the first time combined with field‐amplified sample injection (FASI) in CE to determine four β2‐agonists (cimbuterol, clenbuterol, mabuterol, and mapenterol) in bovine urine. Optimum BGE consisted of 20 mM borate buffer and 0.1 mM SDS. Using salting‐out extraction, β2‐agonists were extracted into ACN that was then used as the disperser solvent in DLLME–SFO. Optimum DLLME–SFO conditions were: 1.0 mL ACN, 50 μL 1‐undecanol (extraction solvent), total extraction time 1.5 min, no salt addition. Back extraction into an aqueous solution (pH 2.0) facilitated direct injection of β2‐agonists into CE. Compared to conventional CZE, DLLME–SFO–FASI–CE achieved sensitivity enhancement factors of 41–1046 resulting in LODs in the range of 1.80–37.0 μg L?1. Linear dynamic ranges of 0.15–10.0 mg L?1 for cimbuterol and 15–1000 μg L?1 for the other analytes were obtained with coefficients of determination (R2) ≥ 0.9901 and RSD% ≤5.5 (n = 5). Finally, the applicability of the proposed method was successfully confirmed by determination of the four β2‐agonists in spiked bovine urine samples and accuracy higher than 96.0% was obtained. 相似文献
150.
Photocatalytic Hydrogen Evolution by Oleic Acid‐Capped CdS,CdSe, and CdS0.75Se0.25 Alloy Nanocrystals 下载免费PDF全文
Emre Aslan Okan Birinci Abdalaziz Aljabour Faruk Özel Ilker Akın Dr. Imren Hatay Patir Dr. Mahmut Kus Prof. Dr. Mustafa Ersoz 《Chemphyschem》2014,15(13):2668-2671
Photocatalytic generation of hydrogen by using oleic acid‐capped CdS, CdSe, and CdS0.75Se0.25 alloy nanocrystals (quantum dots) has been investigated under visible‐light irradiation by employing Na2S and Na2SO3 as hole scavengers. Highly photostable CdS0.75Se0.25 alloy nanocrystals gave the highest hydrogen evolution rate (1466 μmol h?1 g?1), which was about three times higher than that of CdS and seven times higher than that of CdSe. 相似文献