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排序方式: 共有248条查询结果,搜索用时 15 毫秒
51.
Emre Çevik Mehmet Şenel Abdulhadi Baykal M. Fatih Abasıyanık 《Current Applied Physics》2013,13(8):1611-1619
An amperometric phenol biosensor was constructed by using poly(glycidylmethacrylate-co-vinyl ferrocene) grafted iron oxide nanoparticles for detection of different phenolic compounds (catechol, aminophenol, phenol, p-cresol, pyrogallol). The poly(glycidylmethacrylate-co-vinyl ferrocene) and nanoparticles were characterized by Fourier transform infrared (FT-IR), X-ray diffraction (XRD) and transmission electron microscopy (TEM). The copolymer grafted iron oxide nanoparticles and Horseradish peroxidase (HRP) were covalently attached on gold (Au) electrode surface. The effect of pH, temperature and characteristic features such as; reusability and storage stability were studied. The electrode showed good response time within ~3 s. The electrocatalytic response showed a linear dependence on the phenolic compounds concentration ranging from 0.5 to 17.0 mM. 相似文献
52.
Values of Dirichlet <Emphasis Type="Italic">L</Emphasis>-functions,Gauss sums and trigonometric sums
Emre Alkan 《The Ramanujan Journal》2011,26(3):375-398
Motivated by the classical work of Ramanujan and recent work of Berndt and Zaharescu, we establish certain infinite families
of identities relating values of Dirichlet L-functions at positive integers to Gauss sums and trigonometric sums twisted with characters. 相似文献
53.
Musa Özil Fatih İslamoğlu Emre Menteşe Bahittin Kahveci 《Helvetica chimica acta》2010,93(10):1967-1974
The novel 4‐amino‐ or 4‐aryl‐substituted 2,4‐dihydro‐5‐[(4‐trifluoromethyl)phenyl]‐3H‐1,2,4‐triazol‐3‐ones 3a – 3g were synthesized by reaction of N‐(ethoxycarbonyl)‐4‐(trifluoromethyl)benzenehydrazonic acid ethyl ester ( 2 ) and primary amines or hydrazine by microwave irradiation. Compounds 3a – 3g were potentiometrically titrated with tetrabutylammonium hydroxide (Bu4NOH) in four nonaqueous solvents, i.e., iPrOH, tBuOH, MeCN, and N,N‐dimethylformamide (DMF). Also half‐neutralization potential values and the corresponding pKa values were determined in all cases. 相似文献
54.
Emre Alkan Florin Stan Alexandru Zaharescu 《Proceedings of the American Mathematical Society》2006,134(10):2807-2815
Generalizing a classical problem of Lehmer, in this paper we provide an asymptotic result for the number of Lehmer -tuples.
55.
While raising debt on behalf of the government, public debt managers need to consider several possibly conflicting objectives and have to find an appropriate combination for government debt taking into account the uncertainty with regard to the future state of the economy. In this paper, we explicitly consider the underlying uncertainties with a complex multi-period stochastic programming model that captures the trade-offs between the objectives. The model is designed to aid the decision makers in formulating the debt issuance strategy. We apply an interactive procedure that guides the issuer to identify good strategies and demonstrate this approach for the public debt management problem of Turkey. 相似文献
56.
A defining set of a t-(v, k, λ) design is a partial design which is contained in a unique t-design with the given parameters. A minimal defining set is a defining set, none of whose proper partial designs is a defining
set. This paper proposes a new and more efficient algorithm that finds all non-isomorphic minimal defining sets of a given
t-design. The complete list of minimal defining sets of 2-(6, 3, 6) designs, 2-(7, 3, 4) designs, the full 2-(7, 3, 5) design,
a 2-(10, 4, 4) design, 2-(10, 5, 4) designs, 2-(13, 3, 1) designs, 2-(15, 3, 1) designs, the 2-(25, 5, 1) design, 3-(8, 4,
2) designs, the 3-(12, 6, 2) design, and 3-(16, 8, 3) designs are given to illustrate the efficiency of the algorithm. Also,
corrections to the literature are made for the minimal defining sets of four 2-(7, 3, 3) designs, two 2-(6, 3, 4) designs
and the 2-(21, 5, 1) design. Moreover, an infinite class of minimal defining sets for 2-((v) || 3){v\choose3} designs, where v ≥ 5, has been constructed which helped to show that the difference between the sizes of the largest and the smallest minimal
defining sets of 2-((v) || 3){v\choose3} designs gets arbitrarily large as v → ∞. Some results in the literature for the smallest defining sets of t-designs have been generalized to all minimal defining sets of these designs. We have also shown that all minimal defining
sets of t-(2n, n, λ) designs can be constructed from the minimal defining sets of their restrictions when t is odd and all t-(2n, n, λ) designs are self-complementary. This theorem can be applied to 3-(8, 4, 3) designs, 3-(8, 4, 4) designs and the full 3-(8 || 4)3-{8 \choose 4} design using the previous results on minimal defining sets of their restrictions. Furthermore we proved that when n is even all (n − 1)-(2n, n, λ) designs are self-complementary. 相似文献
57.
Niyazi Bicak Bunyamin Karagoz Dilek Emre 《Journal of polymer science. Part A, Polymer chemistry》2006,44(6):1900-1907
Copper‐mediated atom transfer radical polymerization (ATRP) is presented as a versatile tool for the graft copolymerization of 2‐ethyl hexylacrylate with poly(vinyl chloride) (PVC) in an aqueous suspension. The appreciable solubility of PVC in 2‐ethyl hexylacrylate (30%) at temperatures around 130 °C makes grafting of the monomer possible from labile chlorines of PVC in aqueous suspensions without the use of additional solvent. The first‐order kinetics (rate constant k = 4.2 × 10?6 s?1) of the mass percentage increase reveals a typical ATRP fashion of the graft copolymerization at low conversions. The use of a completely organosoluble copper(I) complex of hexylated triethylene tetramine, in combination with α‐methylcellulose as a stabilizer, makes the graft copolymerization possible in a dispersed organic phase. Nearly spherical, green particles can be obtained with moderate stirring rates (1000 rpm) in high graft yields. Although the kinetics of the reaction deviates from the first order at high conversions, reasonable graft yields (146%) can be attained within a reaction period of 24 h. In this study, the reaction conditions of the grafting have been studied, and graft products have been confirmed by common techniques such as 1H NMR, gel permeation chromatography, and differential scanning calorimetry. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1900–1907, 2006 相似文献
58.
A method for calculating the probability of customer demand satisfaction in production–inventory–customer systems with Markovian machines, finite finished goods buffers, and random demand is developed. Using this method, the degradation of this probability as a function of demand variability is quantified. In addition, it is shown by examples that the probability of customer demand satisfaction depends primarily on the coefficient of variation, rather than on the complete distribution, of the demand. 相似文献
59.
The advent of parallel computing technology and low-cost computing hardware has facilitated the adoption of high-performance
computing tools for the analysis of sedimentation data. Over the past 15 years, we have developed the UltraScan software (Demeler
et al., ) to support sedimentation analysis, experimental design, and data management. We describe here recent extensions and advances
in methodology that have been adapted in UltraScan. High-performance computing methods implemented on parallel supercomputers
utilizing grid computing technology are used to analyze sedimentation experiments at much higher resolution than was previously
possible. We discuss the implementation of parallel computing in three novel algorithms used in UltraScan for modeling of
sedimentation velocity experiments and provide guidelines for effective data analysis. 相似文献
60.
Alemdar Bayraktar Ahmet Can Altunişik Barış Sevim Murat Emre Kartal Temel Türker Yasemin Bilici 《Nonlinear dynamics》2009,58(4):655-673
In this paper, it is aimed to compare the near- and far-fault ground motion effects on the nonlinear dynamic response of dams
including dam–reservoir–foundation interaction. Two different types of dams, which are concrete arch and concrete faced rockfill
dams, are selected to investigate the near- and far-fault ground motion effects on the dam responses. The behavior of reservoir
water is taken into account using Lagrangian approach. The Drucker–Prager material model is employed in nonlinear analyses.
Near and far-fault strong ground motion records, which have approximately identical peak ground accelerations, of Loma Prieta
(1989) earthquake are selected for the analyses. Displacements, maximum and minimum principal stresses are determined using
the finite element method. The displacements and principal stresses obtained from the analyses of dams subjected to each fault
effect are compared with each other. It is clearly seen that there is more seismic demand on displacements and stresses when
the dam is subjected to near-fault ground motion. 相似文献