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71.
72.
Nonlinear Dynamics - Substitution Box (S-Box) is one of the most significant structures used to create an encryption which is strong and resistant against attacks in block encryption algorithms.... 相似文献
73.
Gökhan Alpaslan Mustafa Macit Ahmet Erdönmez Orhan Büyükgüngör 《Structural chemistry》2011,22(3):681-690
The Schiff base compound (Z)-1-((4-phenylamino)phenylamino)methylene)naphthalen-2(1H)-one has been synthesized and characterized by IR, UV–Vis, and X-ray single-crystal determination. Molecular geometry from
X-ray experiment of the title compound in the ground state have been compared using the Hartree–Fock (HF) and density functional
method (B3LYP) with 6−31G(d,p) basis set. Calculated results show that density functional theory DFT and HF can well reproduce
the structure of the title compound. Using the time-dependent density functional theory (TD-DFT) and Hartree–Fock (TD-HF)
methods, electronic absorption spectra of the title compound have been predicted and a good agreement with the TD-DFT method
and experimental ones is determined. The energetic behavior of the title compound in solvent media has been examined using
B3LYP method with the 6−31G(d,p) basis set by applying the polarizable continuum model (PCM). The total energy of the title
compound decreases with increasing polarity of the solvent. In addition, DFT calculations of the title compound, molecular
electrostatic potential (MEP), natural bond orbital analysis (NBO), and non-linear optical (NLO) properties were performed
at B3LYP/6−31G(d,p) level of theory. 相似文献
74.
75.
A heuristic for obtaining an initial solution for the transportation problem is presented. Comparison of findings obtained by the new heuristic and Vogel's approximation method (VAM) are tabulated for 480 examples. Superior performance of the new heuristic over VAM is discussed in terms of total costs obtained, number of iterations required to reach the final solution, and CPU time required to solve the problems. Experimental design aspects are also presented. 相似文献
76.
We have examined a solution to the FRW model of the Einstein and de Sitter Universe, often termed the standard model of cosmology, using wide values for the normalized cosmic constant (Ω∧) and spacetime curvature (Ω
k
) with proposed values of normalized matter density. These solutions were evaluated using a combination of the third type of elliptical equations and were found to display critical points for redshift z, between 1 and 3, when Ω∧ is positive. These critical points occur at values for normalized cosmic constant higher than those currently thought important, though we find this solution interesting because the Ω∧ term may increase in dominance as the Universe evolves bringing this discontinuity into importance. We also find positive Ω∧tends towards attractive at values of z which are commonly observed for distant galaxies. 相似文献
77.
Schirmeisen A Taskiran A Fuchs H Bracht H Murugavel S Roling B 《Physical review letters》2007,98(22):225901
The hopping movements of mobile ions in a nanostructured LiAlSiO4 glass ceramic are characterized by time-domain electrostatic force spectroscopy (TDEFS). While the macroscopic conductivity spectra are governed by a single activation energy, the nanoscopic TDEFS measurements reveal three different dynamic processes with distinct activation energies. Apart from the ion transport processes in the glassy and crystalline phases, we identify a third process with a very low activation energy, which is assigned to ionic movements at the interfaces between the crystallites and glassy phase. Such interfacial processes are believed to play a key role for obtaining high ionic conductivities in nanostructured solid electrolytes. 相似文献
78.
79.
Based on von Mises’ yield criterion, deformation theory of plasticity and Swift’s hardening law, elasto-plastic deformation of variable thickness annular disks subjected to external pressure is studied. A nonlinear shooting method using Newton’s iterations with numerically approximated tangent is designed for the solution of the problem. Considering a thickness profile in the form of a general parabolic function, the condition of occurrence of plastic deformation at the inner and outer edges of the annular disk is investigated. A critical disk profile is determined and the corresponding elastic–plastic stresses as well as the residual stress distribution upon removal of the applied pressure are computed and discussed. 相似文献
80.
Electrochemical Detection of a Cancer Biomarker mir‐21 in Cell Lysates Using Graphene Modified Sensors 下载免费PDF全文
Tugba Kilic Arzum Erdem Yasemin Erac M. Ozgur Seydibeyoglu Salih Okur Mehmet Ozsoz 《Electroanalysis》2015,27(2):317-326
In the present study, the voltammetric and impidimetric detection of microRNA‐21, mir‐21 from cell lysates was investigated for the first time by using graphene modified disposable pencil graphite electrodes (GME). The surface characterization of GME was performed via electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM). Upon passive adsorption of inosine substituted antimicroRNA‐21, antimir‐21 probe, InP, onto the surface of GME and then solid phase hybridization of InP with mir‐21, the target, the electrochemical detection was performed by using Differential Pulse Voltammetry (DPV) and EIS techniques. This developed biosensor, GME has presented a 2.77 times lower detection limit of 2.09 µg/mL (3.12 pmol) with respect to unmodified pencil graphite electrode (GE). Moreover it is capable of analyzing mir‐21 in the cell lysates of mir‐21 positive breast cancer cell line (MCF‐7) contrast to mir‐21 negative hepatoma cell line (HUH‐7). The proposed electrochemical yes‐no system does not require any purification and/or amplification step prior to fast detection of mir‐21 from real samples. 相似文献