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51.
In view of CdS growth is very impotent for technological importance especially solar applications; synthesis of this material remains a topic of great interest for researchers by means of an economically and technically viable method. In the present paper, Cd/CdS/n–Si/Au–Sb sandwich structure has been grown by Successive Ionic Layer Adsorption and Reaction (SILAR) technique. For investigating the structural properties, X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDAX) measurements have been performed and it has been seen that films exhibit polycrystalline behavior. The capacitance–voltage (C–V) and conductance/w-voltage (G/w–V) characteristics of Cd/CdS/n–Si/Au–Sb structure have been investigated by considering series resistance and interface states effects. These measurements have been done in the −4 V, 4 V voltage range and in the frequency range of 10 kHz–3 MHz at room temperature. It is seen that, the series resistance (Rs) and interface state density have been strongly depend on frequency. The barrier height, donor concentration, diffusion potential parameters have been determined from the linear C−2–V plot. The barrier height values are obtained between 0.495 and 0.796 eV and doping density values have been ranged from 1.455 × 1014 to 1.999 × 1014 cm−3respectively. The capacitance–frequency (C–f) and conductance/w-frequency (G/w–f) characteristics of Cd/CdS/n–Si/Au–Sb structures have been measured at the various biases 0.00–0.14 V at room temperature. The energy distribution of the interface states (Nss) and their relaxation time (τ) have been determined from the forward bias capacitance–frequency characteristics. The Nss and τ values have ranged from 2.01 × 1012 cm−2 eV−1and 9.68 × 10−4 s in (Ec-0.45) eV–2.86 × 1013 cm−2 eV−1 and 3.81 × 10−4 s in (Ec-0.75) eV, respectively. 相似文献
52.
Lavinia Corina Ciungu George Georgescu Claudia Mureşan 《Archive for Mathematical Logic》2013,52(3-4):335-376
States have been introduced on commutative and non-commutative algebras of fuzzy logics as functions defined on these algebras with values in [0,1]. Starting from the observation that in the definition of Bosbach states there intervenes the standard MV-algebra structure of [0,1], in this paper we introduce Bosbach states defined on residuated lattices with values in residuated lattices. We are led to two types of generalized Bosbach states, with distinct behaviours. Properties of generalized states are useful for the development of an algebraic theory of probabilistic models for non-commutative fuzzy logics. 相似文献
53.
?. Ate? G. Tekeli G. ?elik E. Ak?n M. Ta?er 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,54(1):21-24
The electric dipole oscillator strengths for multiplet and
individual lines between some doublet and quartet levels have been
calculated using the weakest bound electron potential model theory (WBEPMT)
in singly ionized oxygen. We employed both numerical Coulomb approximation
(NCA) wave functions and numerical non-relativistic Hartree-Fock (NRHF) wave
functions for expectation values of radii in determination of parameters.
The calculated oscillator strengths have been compared with available
theoretical and experimental results. A good agreement with results in
literature has been obtained. Moreover, oscillator strengths not existing in
the literature for some highly excited levels have been obtained using this
method.
Electronic supplementary material Supplementary Online Material 相似文献
54.
Ulaş Sabahattin Gökay Muhammad Zakwan Abdullah Demir Ali Serpengüzel 《Fiber and Integrated Optics》2016,35(1):38-46
In this article, Fano lineshape whispering gallery modes were observed in the light scattering spectrum of a silicon microsphere in near-infrared telecommunication wavelengths. A simple model is presented to explain the transition from Lorentzian lineshape to the Fano lineshape resonances with the coupled-mode theory of multiple whispering gallery modes. Polar mode spacing of 0.23 nm is observed in the spectra, which correlates well with the calculated value. The quality factor of the Lorentzian and Fano resonances are on the order of 105. By using an appropriate interface design for the microsphere coupling geometries, Fano lineshape optical resonances herald novel device applications for silicon volumetric lightwave circuits. 相似文献
55.
In this article the authors give the relation between a finitely-generated torsionfree Dedekind module M over a domain R and prime submodules of the 𝒪(M)-module M and the ring 𝒪(M). They also prove that M is a finitely-generated torsionfree Dedekind module over a domain R if and only if every semi-maximal submodule of R-module M is invertible. 相似文献
56.
Recently, O’Hara, Pillay and Xu (Nonlinear Anal. 54, 1417–1426, 2003) considered an iterative approach to finding a nearest common fixed point of infinitely many nonexpansive mappings in a Hilbert
space. Very recently, Takahashi and Takahashi (J. Math. Anal. Appl. 331, 506–515, 2007) introduced an iterative scheme by the viscosity approximation method for finding a common element of the set of solutions
of an equilibrium problem and the set of fixed points of a nonexpansive mapping in a Hilbert space. In this paper, motivated
by these authors’ iterative schemes, we introduce a new iterative approach to finding a common element of the set of solutions
of an equilibrium problem and the set of common fixed points of infinitely many nonexpansive mappings in a Hilbert space.
The main result of this work is a strong convergence theorem which improves and extends results from the above mentioned papers. 相似文献
57.
Nilgün YenerCengiz Biçer Mü?erref Önal Yüksel Sar?kaya 《Applied Surface Science》2012,258(7):2534-2539
To distinguish the ion exchanged and physically adsorbed methylene blue cations (MB+) on ionic surfaces, acid activated bentonite samples were used as porous adsorbents. A natural calcium bentonite (CaB) sample from Enez/Edirne, Turkey, was acid activated at 90 °C for 16 h with various HCl/CaB ratios. The irreversible exchange and physical adsorption of MB+ cations on the ionic solids have simultaneously occurred. The ion exchanged (mex) and physically adsorbed (mad) MB+ contents were obtained as the values of sorption capacity at c = 0 and the increase to a plateaus of adsorption isotherms, respectively. The mad value was taken to be monolayer adsorption capacity. Cation exchange capacity (CEC) and specific surface area (SMB) for each sample were calculated from the mex and mad values, respectively. Also, the BET specific surface areas (SBET) and pore size distribution were determined from low temperature nitrogen adsorption/desorption data. A linear correlation between the SMB and SBET values was found. 相似文献
58.
Seda Ünlü Göknur Yaşa Atmaca Fikriye Tuncel Elmalı Ali Erdoğmuş 《Photochemistry and photobiology》2023,99(5):1233-1239
Although the sonophotodynamic method has an effective therapeutic outcome for anticancer treatment compared with the photodynamic method, there are not enough related studies in the literature and this study aims to contribute to the development of sonophotodynamic studies. For this purpose, the Schiff base substituted silicon phthalocyanines were designed and synthesized as effective sensitizer candidates and the photophysicochemical and sonophotochemical features of the phthalocyanines were examined to increase singlet oxygen efficiency. The calculated ΦΔ values indicate that the contribution of substituent groups improved the production of singlet oxygen compared with silicon (IV) phthalocyanine dichloride (SiPcCI2) and also the sonophotochemical applications increased the singlet oxygen yields. The ΦΔ values (ΦΔ = 0.76 for axially bis-{4-[(E)-(pyridin-3-ylimino)methyl]phenol} substituted silicon (IV) phthalocyanine ( 2a ), 0.68 for axially bis-4-[(E)-{[(pyridin-3-yl)methyl]imino}methyl]phenol substituted silicon (IV) phthalocyanine ( 2b ) in photochemical study) reached to ΦΔ = 0.98 for 2a , 0.94 for 2b in sonophotochemical study. This article will enrich the literature on increasing singlet oxygen yield. 相似文献
59.
60.
A copolymer gel has been synthesized from N-vinylcaprolactam and dodecyl methacrylate in ethanol using the free radical cross-linking polymerization method. Characterizations of the gel were performed by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and thermal gravimetric analysis (TGA) techniques. Swelling behavior of the gel was investigated in heptane, toluene, and their binary mixtures with different compositions. Swelling value in toluene is higher than that in heptane and swelling value increases with the increasing initial content of toluene in the binary mixture with heptane. The swelling values are correlated by the first- and second-order differential equations, and the best model correlating the experimental results is a second-order one. Diffusion coefficients have also been calculated for heptane and toluene at each concentration by power-law and first-order equations. While the diffusion mechanism of the gel in heptane is a Fickian one, the gel swelled in toluene exhibits a non-Fickian character. Diffusion mechanisms of the gels in binary mixtures are much more complicated. Because of the higher swelling degree in toluene compared to that in heptane, selectivity of the gel in different {heptane + toluene} mixtures with selectivity close to 1 has also been taken into consideration. 相似文献