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221.
222.
Y. Kaya 《Siberian Mathematical Journal》2006,47(3):452-458
Let f: M m → ? m+1 be an immersion of an orientable m-dimensional connected smooth manifold M without boundary and assume that ξ is a unit normal field for f. For a real number t the map f tξ: M m → ? m+1 is defined as f tξ(p) = f(p) + tξ(p). It is known that if f tξ is an immersion, then for each p ∈ M the number of the focal points on the line segment joining f(p) to f tξ(p) is a constant integer. This constant integer is called the index of the parallel immersion f tξ and clearly the index lies between 0 and m. In case f: $\mathbb{S}^m \to \mathbb{R}^{m + 1} $ is an immersion, we study the presence of a component of index μ in the push-out space Ω(f). If there exists a component with index μ = m in Ω(f) then f is known to be a strictly convex embedding of $\mathbb{S}^m $ . We reveal the structure of Ω(f) when $f(\mathbb{S}^m )$ is convex and nonconvex. We also show that the presence of a component of index μ in Ω(f) enables us to construct a continuous field of tangent planes of dimension μ on $\mathbb{S}^m $ and so we see that for certain values of μ there does not exist a component of index μ in Ω(f). 相似文献
223.
We study the oscillation of a system of two first order nonlinear equations on time scales. This form includes the classical Emden-Fowler differential equation and many of its extensions. We generalize some well-known results of Atkinson, Bohner, Erbe, Peterson and others. We illustrate the results by several examples, including a superlinear Emden-Fowler dynamic system. 相似文献
224.
Nucleation, growth and sintering of Pd deposited on an ultra-thin silica film were studied by scanning tunneling microscopy and infrared reflection absorption spectroscopy. No preferential nucleation of Pd on the silica surface was observed both at 90 and 300 K deposition. When adsorbed on Pd clusters formed at 90 K, CO causes a strong sintering effect even at this temperature. The results are rationalized on the basis of a high mobility of Pd carbonyl-like species on the silica film. At a given Pd coverage, the extent of CO induced sintering cannot be achieved by annealing in vacuum. In addition, vacuum sintering, which commences above 700 K, goes simultaneously with interdiffusion of Pd and support. 相似文献
225.
Simulation of intrinsic parameter fluctuations in decananometer and nanometer-scale MOSFETs 总被引:1,自引:0,他引:1
Asenov A. Brown A.R. Davies J.H. Kaya S. Slavcheva G. 《Electron Devices, IEEE Transactions on》2003,50(9):1837-1852
Intrinsic parameter fluctuations introduced by discreteness of charge and matter will play an increasingly important role when semiconductor devices are scaled to decananometer and nanometer dimensions in next-generation integrated circuits and systems. In this paper, we review the analytical and the numerical simulation techniques used to study and predict such intrinsic parameters fluctuations. We consider random discrete dopants, trapped charges, atomic-scale interface roughness, and line edge roughness as sources of intrinsic parameter fluctuations. The presented theoretical approach based on Green's functions is restricted to the case of random discrete charges. The numerical simulation approaches based on the drift diffusion approximation with density gradient quantum corrections covers all of the listed sources of fluctuations. The results show that the intrinsic fluctuations in conventional MOSFETs, and later in double gate architectures, will reach levels that will affect the yield and the functionality of the next generation analog and digital circuits unless appropriate changes to the design are made. The future challenges that have to be addressed in order to improve the accuracy and the predictive power of the intrinsic fluctuation simulations are also discussed. 相似文献
226.
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228.
1,8-Bis(3,6-di(thiophen-3-yl)-9H-carbazol-9-yl)octane (BDTCO) was synthesized via Ullmann and Suzuki couplings. Additionally, its homopolymer and copolymers with 3,4-ethylenedioxythiophene (EDOT), pyrrole (Py) and thiophene (Th) were synthesized and coated onto an ITO–glass surface via electrochemical oxidative polymerization. The spectroelectrochemical and electrochromic properties of the polymers were also investigated. The switching ability of these polymers was measured as the percent transmittance (T%) at their point of maximum contrast. Moreover, the polymer of BDTCO (P-BDTCO) was successfully synthesized through FeCl3 oxidative polymerization. The compounds were characterized by FT-IR, NMR and X-ray Photoelectron Spectroscopy (XPS), and their thermal stabilities were determined via TG measurements. The solid state conductivities of the polymeric films coated onto the ITO–glass surface were measured via the four point probe technique using an electrometer. In addition, the surface morphological properties were investigated by Scanning Electron Microscopy (SEM) for different magnifications. 相似文献
229.
Ahmadivand Arash Sinha Raju Karabiyik Mustafa Vabbina Phani Kiran Gerislioglu Burak Kaya Serkan Pala Nezih 《Journal of nanoparticle research》2017,19(1):1-11
Journal of Nanoparticle Research - La(Ni0.75W0.25)O3 perovskite oxide was prepared via the sol–gel Pechini route. The pure crystalline phase was verified via X-ray diffraction measurements... 相似文献
230.
A high‐level theoretical study into the atmospheric phase hydration,bond dissociation enthalpies,and acidity of aldehydes 下载免费PDF全文
CBS‐Q//B3, G4(MP2), and G4 composite method calculations were used to estimate atmospheric phase standard state (298.15 K, 1 atm) free energies of hydration (ΔhydrG°(g)), hydration equilibrium constants (log Khydr,(g)), bond dissociation enthalpies (BDEs), and enthalpies (ΔdH°(g)) and free energies (ΔdG°(g)) of aldehydic proton acid dissociation for various substituted aldehydes with electron withdrawing and electron releasing groups. Good quality log Khydr,(g) correlations with the Swain–Lupton resonance effect parameters R and R+ were found, allowing extension of the model to predict log Khydr,(g) values for 487 substituted aldehydes having available R‐values and 108 substituted aldehydes having available R+ values. Good correlations were also found between experimental aqueous phase hydration equilibrium constants (log Khydr,(aq)) and summative R/R+ values for peripheral substituents on a range of carbonyl derivatives (aldehydes, ketones, esters, and amides), suggesting that the structure–reactivity modeling approach can be extended to include all possible combinations of R1C(O)R2 carbonyl substitution in both gas and aqueous systems. Computationally derived BDEs and ΔdH°(g)/ΔdG°(g) were in good agreement with the limited experimental and theoretical datasets. BDEs did not generally correlate with any of the Hammett substituent constants or Swain–Lupton parameters considered. Gas phase acidities exhibited high correlation coefficients with Hammett inductive substituent constants (σI) and field effect parameters (F), allowing these to be employed as surrogates for estimating the gas phase aldehydic proton acidities of a larger potential compound range. The resulting models will be of use in predicting the environmental behavior for a broad range of environmentally relevant compounds containing carbonyl functionalities. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献