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81.
In this research, we present a new approach based on variational iteration method for solving nonlinear time-fractional partial differential equations in large domains. The convergence of the method is shown with the aid of Banach fixed point theorem. The maximum error bound is specified. The optimal value of auxiliary parameter is obtained by use of residual error function. The fractional derivatives are taken in the Caputo sense. Numerical examples that involve the time-fractional Burgers equation, the time-fractional fifth-order Korteweg–de Vries equation and the time-fractional Fornberg–Whitham equation are examined to show the appropriate properties of the method. The results reveal that a new approach is very effective and convenient. 相似文献
82.
Synthesis of a series of 3-acetylcoumarin-derived chalcones (1a–16a) was catalyzed with Amberlyst 26A in ethanol. Using reusable Amberlyst 26A and biobased solvent ethanol make this method highly ecofriendly and simple. Amberlyst 26A was found to be a highly effective catalyst for cross aldol reaction. The results shown that the method is operationally simple to implement with a wide scope of substrates. 相似文献
83.
Özge Dağlı Dursun Ali Köse Gülçin Alp Avcı Onur Şahin 《Journal of Thermal Analysis and Calorimetry》2017,129(3):1389-1402
Coordination complexes of transition metal cations (CoII, NiII, CuII and ZnII) containing coumarilate and N,N′-diethylnicotinamide were synthesized. The structural characterization and thermal behaviour analysis of novel samples synthesized were conducted through elemental analysis, magnetic susceptibility, solid-state UV–Vis, direct and injection probe mass spectra, FTIR spectra, thermoanalytic TG-DTG/DTA and single crystal X-ray diffraction methods. The structural details of single crystals of [Co(dena)2(H2O)4](coum)2 (I) and [Cu(coum)2(dena)2(H2O)2] (III) complexes were resolved completely. Moreover, the results of analysis obtained for [Ni(coum)2(dena)2(H2O)2] (II) and [Zn(dena)2(H2O)4](coum)2 (IV) complexes were interpreted considering the samples with crystal structures defined and made assumptions about the structural details. It was determined that the complex of CoII metal cation has salt-type structure and the coordination number of metal is accomplished to six as the sum of 4 mol of water and also 2 mol of N,N′-diethylnicotinamide ligands in trans position located within the coordination sphere. It was observed that 2 mol of coumarilate anions are located outside the coordination sphere and have stabilized to the charge (2+) of metal. The CuII complex has totally molecular structure, and the coordination sphere of metal cation was 6 as the sum of 2 mol of water, 2 mol of N,N′-diethylnicotinamide and 2 mol of monoanionic monodentate coumarilate ligands. All ligands have been located in –trans position. The geometry of both complex structures is distorted octahedral. It is assumed that the NiII complex structure is isostructural with CuII complex structure and also does ZnII complex with CoII structure. It was determined that the decomposition products obtained from thermal analysis are the oxides of related metal cations. 相似文献
84.
Abbasi Akbar Kurnaz Asley Turhan Şeref Mirekhtiary Fatemeh 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(1):203-210
Journal of Radioanalytical and Nuclear Chemistry - Due to increasing concern about environmental radiological protection, radioactivity concentrations of 226Ra, 232Th, 40K and 137Cs in surface soil... 相似文献
85.
Niyazi Onur Bakır 《Annals of Operations Research》2011,187(1):5-22
This paper presents a game theoretic model that analyzes resource allocation strategies against an adaptive adversary to secure
cargo container transportation. The defender allocates security resources that could interdict an unauthorized weapon insertion
inside a container. The attacker observes the defender’s security strategy and chooses a site to insert the weapon. The attacker’s
goal is to maximize the probability that the weapon reaches its target. The basic model includes a single container route.
The results in the basic model suggest that in equilibrium the defender should maintain an equal level of physical security
at each site on the cargo container’s route. Furthermore, the equilibrium levels of resources to interdict the weapon overseas
increase as a function of the attacker’s capability to detonate the weapon remotely at a domestic seaport. Investment in domestic
seaport security is highly sensitive to the attacker’s remote detonation capability as well. The general model that includes
multiple container routes suggests that there is a trade-off between the security of foreign seaports and the physical security
of sites including container transfer facilities, container yards, warehouses and truck rest areas. The defender has the flexibility
to shift resources between non-intrusive inspections at foreign seaports and physical security of other sites on the container
route. The equilibrium is also sensitive to the cost effectiveness of security investments. 相似文献
86.
Huseyin Onur Mete Yanfang Shen Zelda B. Zabinsky Seksan Kiatsupaibul Robert L. Smith 《Journal of Global Optimization》2011,50(4):597-627
We develop new Markov chain Monte Carlo samplers for neighborhood generation in global optimization algorithms based on Hit-and-Run.
The success of Hit-and-Run as a sampler on continuous domains motivated Discrete Hit-and-Run with random biwalk for discrete
domains. However, the potential for efficiencies in the implementation, which requires a randomization at each move to create
the biwalk, lead us to a different approach that uses fixed patterns in generating the biwalks. We define Sphere and Box Biwalks that are pattern-based and easily implemented for discrete and
mixed continuous/discrete domains. The pattern-based Hit-and-Run Markov chains preserve the convergence properties of Hit-and-Run
to a target distribution. They also converge to continuous Hit-and-Run as the mesh of the discretized variables becomes finer,
approaching a continuum. Moreover, we provide bounds on the finite time performance for the discrete cases of Sphere and Box
Biwalks. We embed our samplers in an Improving Hit-and-Run global optimization algorithm and test their performance on a number
of global optimization test problems. 相似文献
87.
Zhang X Khimji I Gurkan UA Safaee H Catalano PN Keles HO Kayaalp E Demirci U 《Lab on a chip》2011,11(15):2535-2540
5.3 million American couples of reproductive age (9%) are affected by infertility, among which male factors account for up to 50% of cases, which necessitates the identification of parameters defining sperm quality, including sperm count and motility. In vitro fertilization (IVF) with or without intra cytoplasmic sperm injection (ICSI) has become the most widely used assisted reproductive technology (ART) in modern clinical practice to overcome male infertility challenges. One of the obstacles of IVF and ICSI lies in identifying and isolating the most motile and presumably healthiest sperm from semen samples that have low sperm counts (oligozoospermia) and/or low sperm motility (oligospermaesthenia). Microfluidic systems have shown potential to sort sperm with flow systems. However, the small field of view (FOV) of conventional microscopes commonly used to image sperm motion presents challenges in tracking a large number of sperm cells simultaneously. To address this challenge, we have integrated a lensless charge-coupled device (CCD) with a microfluidic chip to enable wide FOV and automatic recording as the sperm move inside a microfluidic channel. The integrated system enables the sorting and tracking of a population of sperm that have been placed in a microfluidic channel. This channel can be monitored in both horizontal and vertical configuration similar to a swim-up column method used clinically. Sperm motilities can be quantified by tracing the shadow paths for individual sperm. Moreover, as the sperm are sorted by swimming from the inlet towards the outlet of a microfluidic channel, motile sperm that reach the outlet can be extracted from the channel at the end of the process. This technology can lead to methods to evaluate each sperm individually in terms of motility response in a wide field of view, which could prove especially useful, when working with oligozoospermic or oligospermaesthenic samples, in which the most motile sperm need to be isolated from a pool of small number of sperm. 相似文献
88.
In situ complexation reactions between 2,6-bis(3,5-dimethylpyrazoyl)pyridine (bdmpp) and some transition metals (Cu2+, Co2+ and Ni2+) were studied with a new method in liquid cell using FT-IR. In this method, the FT-IR spectrum of the solution of ligand was defined as a background, and then the changes in the FT-IR spectra by the addition of the metal salts were investigated. This method allows one to obtain the spectra of the ligand-metal complex before yielding the solid-state product. Complexation ratios (M/L) of these metals with bdmpp were found 1/1, 1/2 and 1/2, for Cu, Co and Ni, respectively. Studying with Mg2+ and Ca2+ ions showed that there were no interaction between bdmpp and these metal ions in methanol. 相似文献
89.
Dursun?Ali?KoseEmail author Hacali?Necefo?lu Onur??ahin Orhan?Büyükgüng?r 《Journal of chemical crystallography》2011,41(3):297-305
Abstract
The compound has been formed by mononuclear [Cu(C9H7O4)2(C6H6N2O)2(H2O)] units in which the metal ion as well as the water ligand lies on a twofold symmetry axis, so that only one acetylsalicylate ligand and one nicotinamide ligand are independent. The distortion from ideal five-coordinate geometries can be described best by the degree of trigonality τ. For a regular square-pyramidal (SQP) geometry the trigonality parameter is 0 and for a trigonal–bipyramidal (TBP) structure it increases to 1. The copper coordination geometry is that of a square pyramid (τ = 0.23), with the N atoms from nicotinamide ligands and the bonded carboxylate O atoms from acetylsalicylate ligands defining the quasi-planar square base. The apical site is occupied by the aqua ligand, a bond which coincides with the twofold symmetry axis and is thus exactly perpendicular to the basal plane. The thermal decomposition takes place in four steps: removing of moisture, dehydration of aqua ligand, the elimination of the nicotinamide (na) ligand and the decomposition of acetyl-groups and oxidation of salicylate ion ligands. In complex, all ligands are coordinated to the metal ion as monodendate. The IR spectra of the intermediate products showed similar results. 相似文献90.
Şeref Kalem Örjan Arthursson Peter Werner 《Applied Physics A: Materials Science & Processing》2013,112(3):555-559
In this paper, we present an analysis for treating the spectroscopic ellipsometry response of Si/Ge superlattices (SLs) with embedded Ge dots. Spectroscopic ellipsometry (SE) measurement at room temperature was used to investigate optical and electronic properties of Si/Ge SLs which were grown on silicon (Si) wafers having 〈111〉 crystallographic orientation. The results of the SE analysis between 200 nm and 1000 nm indicate that the SL system can effectively be described using an interdiffusion/intermixing model by assuming multicrystalline Si and Si1?x Ge x intermixing layers. The electronic transitions deduced from the analysis reveal Si-, Ge- and alloying-related critical energy points. 相似文献