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21.
Moosa Gabeleh 《Quaestiones Mathematicae》2016,39(2):203-215
A new class of noncyclic mappings, called generalized noncyclic relatively nonexpansive, is introduced and used to study the existence of best proximity pairs in the setting of uniformly convex Banach spaces. We also obtain a weak convergence theorem for noncyclic relatively nonexpansive mappings in the setting of Hilbert spaces. 相似文献
22.
This paper describes the measurement of induction time in precipitation of silver nanoparticles at different temperatures and supersaturations, and models it with Smoluchowski's coagulation theory. Silver nanoparticles are synthesized by reaction of silver nitrate with hydrazine in the presence of sodium citrate as stabilizer. The rate of association between clusters is found to depend on temperature and their sizes. The activation energy for the association between two clusters and interfacial tension of silver nanoparticles were also estimated. The results also show that induction time decreases with increasing supersaturation and temperature. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
23.
We derive the coupled-mode equations for a metamaterial fiber Bragg gratings (FBGs). The coupled-mode theory describing wave propagation in periodic structures such as FBG is generalized for studying the transmission and reflection of electromagnetic waves through a FBG containing metamaterial layers. This approach shows that the band gap becomes broader in comparison with a conventional FBG. It is observed that the central frequency of the band gap has a shift in regard of changing metamaterial thickness. We verify this investigation through attaining the transmission and reflection spectra of a conventional FBG while we are setting related parameters. Furthermore, this proposed structure can be applied as a tunable filter. 相似文献
24.
In this study, coupled equations of the motion of a particle in a fluid forced vortex were investigated using the differential transformation method (DTM) with the Pad6 approximation and the differential quadrature method (DO_M). The significant contribution of the work is the introduction of two new, fast and efficient solutions for a spherical particle in a forced vortex that are improvements over the previous numerical results in the literature. These methods represent approximations with a high degree of accuracy and minimal computational effort for studying the particle motion in a fluid forced vortex. In addition, the velocity profiles (angular and radial) and the position trajectory of a particle in a fluid forced vortex are described in the current study. 相似文献
25.
This paper is concerned with the design of a Bayesian network structure that is suitable for operational risk modelling. The model's structure is designed specifically from the perspective of a business unit operational risk manager whose role is to measure, record, predict, communicate, analyse and control operational risk within their unit. The problem domain modelled is a functioning structured finance operations unit within a major Australian bank. The network model design incorporates a number of existing human factor frameworks to account for human error and operational risk events within the domain. The design also supports a modular structure, allowing for the inclusion of many operational loss event types, making it adaptable to different operational risk environments. 相似文献
26.
Therapeutic drug monitoring (TDM), as part of clinical process of medical treatments, is commonly used to maintain 'therapeutic' drug concentrations. TDM is useful to identify the causes of unwanted or unexpected responses, to prevent unnecessary diagnostic testing, to improve clinical outcomes, and even to save lives. The determination of drug concentration in blood samples requires an excellent sample preparation procedure. Recent trends in sample preparation include miniaturization, automation, high-throughput performance, on-line coupling with analytical instruments and low-cost operation through extremely low or no solvent consumption. Microextraction techniques, such as liquid- and solid-phase microextraction, have these advantages over the traditional techniques. This paper reviews the recent developments in microextraction techniques used for drug monitoring in serum, plasma or blood samples. 相似文献
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28.
On Nonstoichiometric Tungsten Compounds. Synthesis and Lattice Constants of WO3? NaWO3 Mixed Crystal Compounds In the range of temperature from 850 to 1300°C sodium tungsten bronzes with the formula NaxWO3 were prepared from a stoichiometric mixture of W, WO3 and Na2WO4. The variation of lattice constant with nominal bronze composition was determined. 相似文献
29.
In this paper, a reduction technique is used to show that some recent results on the existence of best proximity points for various classes of proximal contractions can be concluded from the corresponding results in fixed point theory. 相似文献
30.
A highly efficient photocatalytic reduction of nitroarenes using TiO2/polyethylene glycol 400-water (TiO2/PEG–H2O) is reported. This system at deoxygenated and illuminated (sunlight or violet LED) conditions efficiently reduced nitroarenes using oxalic acid or ammonium formate as a sacrificial electron donor. Reducible functional groups such as chloro, hydroxy, flouro, bromo and carbonyl were intact under the optimized reaction conditions. The 0.1 and 0.5–1 mmol amount of nitroarenes was used under sunlight and violet LED (400 nm) irradiation, respectively. Reusability of the nanotitania was successfully carried out four times. The analyses of the recovered catalyst after five runs including TEM, XRD, TGA and CHN were done and results showed that PEG is located on TiO2; no change in morphology, crystallinity and particle sizes was observed. 相似文献