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In this paper, a novel biologically-inspired algorithm, namely krill herd (KH) is proposed for solving optimization tasks. The KH algorithm is based on the simulation of the herding behavior of krill individuals. The minimum distances of each individual krill from food and from highest density of the herd are considered as the objective function for the krill movement. The time-dependent position of the krill individuals is formulated by three main factors: (i) movement induced by the presence of other individuals (ii) foraging activity, and (iii) random diffusion. For more precise modeling of the krill behavior, two adaptive genetic operators are added to the algorithm. The proposed method is verified using several benchmark problems commonly used in the area of optimization. Further, the KH algorithm is compared with eight well-known methods in the literature. The KH algorithm is capable of efficiently solving a wide range of benchmark optimization problems and outperforms the exciting algorithms.  相似文献   
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Herein we report chemical and electrochemical formation of poly(3‐methoxyethoxythiophene) and its copolymers with aniline, thiophene and pyrrole which give highly conducting polymeric materials. These are soluble in common organic solvents in the conducting state. The response mechanism of these compounds, to a selection of gases and vapours, was investigated using two techniques: measurement of conductance and mass changes using a four probe method and X‐ray fluorescence (XRF) device, respectively. Prepared films were exposed to hydrogen halides, hydrogen cyanide, halogens, monochloroacetic acid (MCAA), 1‐3‐5 trichloromethylbenzene (TCMB), methylbenzyl bromide (MBB), bromoacetone (BA) and cyanogen bromide (CB). These gas sensors may have advantages compared to other sensors in their ability to operate at room temperature, low concentration, stability in air, sufficient diffusion and their selectivity. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
997.
A simple, fast and efficient benign procedure has been developed for one‐pot synthesis of 2‐substituted benzothiazoles in the presence of zirconium(IV) oxide chloride octahydrate (ZrOCl2·8H2O) and anhydrous copper(II) sulfate. The reaction of 2‐aminothiophenol with aldehydes and anhydrides was carried out efficiently in solvent‐free conditions with or without microwave irradiation, and adducts were produced in good to excellent yields. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:136–141, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20191  相似文献   
998.
A double four component Azido-Ugi reaction of isocyanide, TMSN3, aldehyde, and 4,4′-sulfonyldianiline with two amine functional groups in MeOH at 65°C has been described. The synthesis of pharmacologically and structurally interesting compounds with two 1,5-disubstituted tetrazole rings via a reaction from available and inexpensive reagents under a convenient process and mild reaction conditions has been reported. Modifications in the structure of the reaction product could be followed by varying the aldehyde or isocyanide component. The products are new and were well described by Mass, 1H NMR, and 13C NMR spectral studies.  相似文献   
999.
Research on Chemical Intermediates - In this paper, a new application of the Fe3O4@APTMS@Cp2ZrClx(x = 0, 1, 2) MNPs as a robust and highly efficient Pd-free catalytic system in the environmentally...  相似文献   
1000.
The (37MBq) 99mTc-MIBI complex samples were prepared due to ultrasound irradiation technique or boiled water bath method as a standard method. The qualitative and quantitative studies have been performed. The accumulation of 99mTc-MIBI complexes prepared by two above mentioned modalities were approximately 3 ± 0.1 % in the rats’ heart. The ultrasound irradiation technique is recommended to prepared 99mTc-MIBI complex in efficiently amount. Our approach can potentially reduce medical risk to the patient by avoiding any delay in acute therapy particularly for myocardial infarction patients.  相似文献   
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