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101.
Numerical solution of mixed linear integro-differential-difference equation is presented using Chebyshev collocation method. The aim of this article is to present an efficient numerical procedure for solving mixed linear integro-differential-difference equations. Our method depends mainly on a Chebyshev expansion approach. This method transforms mixed linear integro-differential-difference equations and the given conditions into matrix equation which corresponds to a system of linear algebraic equation. The reliability and efficiency of the proposed scheme are demonstrated by some numerical experiments and performed on the computer algebraic system Maple10. 相似文献
102.
Mehmet Sezer Salih Yalçinbaş 《Numerical Methods for Partial Differential Equations》2010,26(3):596-611
In this article, a collocation method is developed to find an approximate solution of higher order linear complex differential equations with variable coefficients in rectangular domains. This method is essentially based on the matrix representations of the truncated Taylor series of the expressions in equation and their derivates, which consist of collocation points defined in the given domain. Some numerical examples with initial and boundary conditions are given to show the properties of the method. All results were computed using a program written in scientific WorkPlace v5.5 and Maple v12. © 2009 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2010 相似文献
103.
ener Salam Aysu Arman Ayem Üzer Belks Ustamehmetolu Esma Sezer Reat Apak 《Electroanalysis》2020,32(5):964-970
Dopamine (DA) is a significant neurotransmitter in the central nervous system, coexisting with uric acid (UA) and ascorbic acid (AA). UA and AA are easily oxidizable compounds having potentials close to that of DA for electrochemical analysis, resulting in overlapping voltammetric response. In this work, a novel molecularly imprinted (MI) electrochemical sensor was proposed for selective determination of DA (in the presence of up to 80‐fold excess of UA and AA), relying on gold nanoparticles (Aunano)‐decorated glassy carbon (GC) electrode coated with poly(carbazole (Cz)‐co‐aniline (ANI)) copolymer film incorporating DA as template (DA imprinted‐GC/P(Cz‐co‐ANI)‐Aunano electrode, DA‐MIP‐Aunano electrode). The DA recognizing sensor electrode showed great electroactivity for analyte oxidation in 0.2 mol L?1 pH 7 phosphate buffer. Square wave voltammetry (SWV) was performed within 10?4–10?5 mol L?1 of DA, of which the oxidation peak potential was observed at 0.16 V. The limit of detection (LOD) and limit of quantification (LOQ) were 2.0×10?6 and 6.7×10?6 mol L?1, respectively. Binary and ternary synthetic mixtures of DA‐UA, DA‐AA and DA‐UA‐AA yielded excellent recoveries for DA. Additionally, DA was quantitatively recovered from a real sample of bovine serum spiked with DA, and determined in concentrated dopamine injection solution. The developed SWV method was statistically validated against a literature potentiodynamic method using a caffeic acid modified‐GC electrode. 相似文献
104.
105.
Hüseyin Karaca Emre Güzel Serdar Sezer Faysal Selimoğlu Bahar Ergezen 《Journal of Coordination Chemistry》2018,71(10):1606-1622
The new peripherally tetra-substituted metallophthalocyanines (MPcs, M=Zn, Co, Ni) bearing the chalcone, (E)-3-(4-hydroxyphenyl)-1-(thiophen-2-yl)prop-2-en-1-one, for dye-sensitized solar cells (DSSCs) were synthesized. FT-IR, 1H NMR, 13C NMR, and UV–Vis spectroscopy techniques were utilized for characterization of all the MPcs. Electrochemical, optical and photovoltaic properties of all the MPcs as sensitizers were examined. Electrochemical studies reveal that while the ZnPc (4) and NiPc (6) give only Pc ring-based redox reactions, the CoPc (5) shows redox reactions based on both the central metal and the ring due to the metal 3d orbitals lying between the Pc HOMO and LUMO. The DSSC based on 5 gave the lowest power conversion efficiency (0.51%), perhaps due to the presence of a redox active central metal ion in the core of the complex, which results in a decrease electron transfer in the device. However, cells based on the other complexes including redox inactive central metal ions, which cannot reduce electron transfer, showed reasonable power conversion efficiencies of 1.27% and 1.11% for 4 and 6, respectively. The slight difference between the efficiencies can be attributed to higher molar extinction coefficient and narrower band gap of 4 than 6, which ensure a higher photocurrent and broader light absorption in the visible region. 相似文献
106.
Yalcin Mustafa Gurhan Unal Sezer 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(1):321-330
Journal of Radioanalytical and Nuclear Chemistry - In this study, the natural radioactivity levels of the ophiolites in the western region of Antalya, their anomaly values, and effects on human... 相似文献
107.
Osman Rasit Isik Mehmet Sezer Zekeriya Guney 《Mathematical Methods in the Applied Sciences》2014,37(5):609-619
The purpose of this study is to present a new collocation method for numerical solution of linear PDEs under the most general conditions. The method is given with a priori error estimate. By using the residual correction procedure, the absolute error can be estimated. Also, one can specify the optimal truncation limit n, which gives better result in any norm ∥ ∥ . Finally, the effectiveness of the method is illustrated in some numerical experiments. Numerical results are consistent with the theoretical results. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
108.
Sideritis niveotomentosa Hub. -Mor. is a local endemic species belonging to the Lamiaceae family. In this study, GC/MS analysis, total antioxidant capacity and anticancer effects of different extracts obtained from S. niveotomentosa were investigated comparatively. Total phenolic contents of extracts were determined by the Folin–Ciocalteu method, total flavonoid contents by aluminum chloride method, and also the free radical scavenging activities of the extracts by DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) assay. The cytotoxic effect of the extracts was studied via MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assay on DLD1, HL60 and ARH77 cell lines. Pro-apoptotic gene expression levels were also tested in the most sensitive cell line ARH77 by Real-Time PCR. The expression levels of 4 pro-apoptotic genes, APAF, BAX, CASP3, and HRK were found to be upregulated in ARH77 cells that were treated extracts. Results showed that methanolic extracts contain more phenolic content than acetone extracts, consistent with DPPH results. As a result, Sideritis niveotomentosa extracts, especially methanolic extracts, are rich in phenolic content and have a strong radical scavenging effect. In addition, the extracts showed selective effects on cell lines. This study is pioneering in terms of future studies, and the findings provide hope for future experimentation. 相似文献
109.
Ali Devin Sezer 《Queueing Systems》2010,64(2):103-117
This note describes an importance sampling (IS) algorithm to estimate buffer overflows of stable Jackson networks with a tree
topology. Three new measures of service capacity and traffic in Jackson networks are introduced and the algorithm is defined
in their terms. These measures are effective service rate, effective utilization and effective service-to-arrival ratio of a node. They depend on the nonempty/empty states of the queues of the network. For a node with
a nonempty queue, the effective service rate equals the node’s nominal service rate. For a node i with an empty queue, it is either a weighted sum of the effective service rates of the nodes receiving traffic directly from
node i, or the nominal service rate, whichever smaller. The effective utilization is the ratio of arrival rate to the effective
service rate and the effective service-to-arrival ratio is its reciprocal. The rare overflow event of interest is the following:
given that initially the network is empty, the system experiences a buffer overflow before returning to the empty state. Two
types of buffer structures are considered: (1) a single system-wide buffer shared by all nodes, and (2) each node has its
own fixed size buffer. The constructed IS algorithm is asymptotically optimal, i.e., the variance of the associated estimator
decays exponentially in the buffer size at the maximum possible rate. This is proved using methods from (Dupuis et al. in
Ann. Appl. Probab. 17(4):1306–1346, 2007), which are based on a limit Hamilton–Jacobi–Bellman equation and its boundary conditions and their smooth subsolutions.
Numerical examples involving networks with as many as eight nodes are provided. 相似文献
110.
In the present work we consider infinite locally finite minimal non-solvable groups, and give certain characterizations. We
also define generalizations of the centralizer to establish a result relevant to infinite locally finite minimal non-solvable
groups. 相似文献