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21.
Cover Picture: Intracellular Modulation of Excited‐State Dynamics in a Chromophore Dyad: Differential Enhancement of Photocytotoxicity Targeting Cancer Cells (Angew. Chem. Int. Ed. 18/2015) 下载免费PDF全文
22.
Designing Excited States: Theory‐Guided Access to Efficient Photosensitizers for Photodynamic Action
23.
Hilmi Demiray 《Applied mathematics and computation》2011,218(5):2294-2299
In the present work, utilizing the two dimensional equations of an incompressible inviscid fluid and the reductive perturbation method we studied the propagation of weakly nonlinear waves in water of variable depth. For the case of slowly varying depth, the evolution equation is obtained as the variable coefficient Korteweg-de Vries (KdV) equation. Due to the difficulties for the analytical solutions, a numerical technics so called “the method of integrating factor” is used and the evolution equation is solved under a given initial condition and the bottom topography. It is observed the parameters of bottom topography causes to the changes in wave amplitude, wave profile and the wave speed. 相似文献
24.
Nezaket ParlakMesut Gür Vedat Ar?Hasan Küçük Tahsin Engin 《Experimental Thermal and Fluid Science》2011,35(1):60-67
In the study, a second law analysis for a steady-laminar flow of water in adiabatic microtubes has been conducted. Smooth microtubes with the diameters between 50 and 150 μm made of fused silica were used in the experiments. Considerable temperature rises due to viscous dissipation and relatively high pressure losses of flow were observed in experiments. To identify irreversibility of flow, rate of entropy generation from the experiments have been determined in the laminar flow range of Re = 20-2200. The second law of thermodynamics was applied to predict the entropy generation. The results of model taken from the literature, proposed to predict the temperature rise caused by viscous heating, correspond well with the experimental data. The second law analysis results showed that the flow characteristics in the smooth microtubes distinguish substantially from the conventional theory for flow in the larger tubes with respect to viscous heating/dissipation (temperature rise of flow) total entropy generation rate and lost work. 相似文献
25.
The replacement of a point dipole and a point quadrupole by a corresponding linear arrangement of two point charges (+q, ?q) and accordingly three point charges (+q, ?2q, +q) is studied with respect to vapour–liquid equilibria. The dependence of saturated liquid density, vapour pressure and heat of vaporization on the choice of the distance d between the charges in the point charge arrangement is analysed. For the studied dipolar two-centre Lennard-Jones (2CLJD) and quadrupolar two-centre Lennard-Jones (2CLJQ) models, d/σ between 1/15 and 1/20 is a reasonable compromise between numerical and physical accuracy, where σ is the Lennard-Jones size parameter. The results are used to derive validated partial charge based models of 59 real fluids from previously published point dipole and point quadrupole based models. 相似文献
26.
The in situ prepared three‐component system Pd(OAc)2–1,3‐dialkylbenzimidazolium chlorides ( 2a – f ) and Cs2CO3 catalyses, quantitatively, the Suzuki cross‐coupling of deactivated aryl chlorides and Heck coupling reactions of aryl bromide and iodide substrates. The 1,3‐dialkylbenzimidazolium salts ( 2a – f ) were characterized by conventional spectroscopic methods and elemental analysis. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
27.
Neslihan Saki Engin U. Akkaya 《Journal of inclusion phenomena and macrocyclic chemistry》2005,53(3):269-273
A novel dimeric calixpyrrole has been synthesized. The dimer forms stable complexes with p-nitrophenolate ion with a concomitant reduction in extinction coefficient. The chromogenic anion is displaced by the addition of various anions like fluoride and acetate. Effective optical sensing of these anions is accomplished using the calixpyrrole dimer. 相似文献
28.
Baris Kiskan Güniz Demiray Yusuf Yagci 《Journal of polymer science. Part A, Polymer chemistry》2008,46(11):3512-3518
Novel side‐chain benzoxazine functional polyvinylchloride (PVC‐Benzoxazine) was synthesized by using “Click Chemistry” strategy. First, approximately 10% of chloro groups of PVC were converted to azido groups by using NaN3 in N,N‐dimethylformamide. Propargyl benzoxazine was prepared independently by a ring closure reaction between p‐propargyloxy aniline, paraformaldehyde, and phenol. Finally, azidofunctionalized PVC was coupled to propargyl benzoxazine with high efficiency by click chemistry. The spectral and thermal analysis confirmed the presence of benzoxazine functionality in the resulting polymer. It is shown that PVC containing benzoxazine undergoes thermally activated curing in the absence of any catalyst forming PVC thermoset with high thermal stability. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3512–3518, 2008 相似文献
29.
In the present work, by employing the non-linear equations of motion of an incompressible, inhomogeneous, isotropic and prestressed thin elastic tube with variable radius and the approximate equations of an inviscid fluid, which is assumed to be a model for blood, we studied the propagation of non-linear waves in such a medium, in the longwave approximation. Utilizing the reductive perturbation method we obtained the variable coefficient Korteweg–de Vries (KdV) equation as the evolution equation. By seeking a progressive wave type of solution to this evolution equation, we observed that the wave speed decreases for increasing radius and shear modulus, while it increases for decreasing inner radius and the shear modulus. 相似文献
30.
Kadriye Ertekin Ozlem Oter Mustafa Ture Serpil Denizalti Engin Cetinkaya 《Journal of fluorescence》2010,20(2):533-540
In this study, a very sensitive and highly selective irreversible optical chemical sensor (optode) for mercury ions was described.
The sensing scheme was based on the interaction of Hg (II) with a newly synthesized fluoroionophore; chloro phenyl imino propenyl
aniline (CPIPA) in plasticized PVC membrane. The sensor membranes were tested for the determination of mercury ion in aqueous
solutions by batch and flow-through methods. The optodes allow determination of Hg (II) in the working range of 1.0 × 10−9–1.0 × 10−5 M with a detection limit of 4.3 ppb. The sensor exhibited excellent selectivity for Hg (II) with respect to several common
alkali, alkaline earth and transition metal ions. The association constant of the 1:1 complex formation for Hg (II) was found
to be Ka = 1.86 × 105 M−1. The CPIPA exhibited high fluorescence quantum yield, long excitation and emission wavelength and high Stokes’ shift values
in the solid matrix which makes it compatible with solid state optics. 相似文献