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991.
992.
Amir Hossein Gandomi Amir Hossein Alavi 《Communications in Nonlinear Science & Numerical Simulation》2012,17(12):4831-4845
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
993.
994.
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
995.
Firouz Matloubi Moghaddam Hossein Ismaili Ghasem Rezanejade Bardajee 《Heteroatom Chemistry》2006,17(2):136-141
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
996.
Negin Dehghan Hossein Nasr-Isfahani Afshin Sarvary Mohammad Bakherad 《Journal of heterocyclic chemistry》2021,58(1):350-356
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
997.
Zeynizadeh Behzad Mousavi Hossein Sepehraddin Farhad 《Research on Chemical Intermediates》2020,46(7):3361-3382
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
998.
Alireza Doroudi Seyyed Mostafa Saadati Hossein Hassan Pour Faramarz Ahmadi Mostafa Erfani Saeed Rezaee Mohammad Javad Khodayar Hamidreza Samaee Behrouz Etesami 《Journal of Radioanalytical and Nuclear Chemistry》2013,298(2):1185-1190
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
999.
Kazem Jeddi Nader Taheri Qazvini Seyed Hassan Jafari Hossein Ali Khonakdar 《Journal of Polymer Science.Polymer Physics》2010,48(19):2065-2071
AC impedance spectroscopy was used to investigate the ionic conductivity of solution cast poly(ethylene oxide) (PEO)/poly(methyl methacrylate) (PMMA) blends doped with lithium perchlorate. At low PEO contents (below overlap weight fraction w*), ionic conductivities are almost low. This could be due to nearly distant PEO chains in blend, which means ion transportation cannot be performed adequately. However, at weight fractions well above w*, a significant increase in ionic conductivity was observed. This enhanced ionic conductivity mimics the PEO segmental relaxation in rigid PMMA matrix, which can be attributed to the accelerated motions of confined PEO chains in PMMA matrix. At PEO content higher than 20 wt % the conductivity measured at room temperature drops due to crystallization of PEO. However by increasing temperature to temperatures well above the melting point of PEO, a sudden increase of conductivity was observed which was attributed to phase transition from crystalline to amorphous state. The results indicate that some PEO/PMMA blends with well enough PEO content, which are structurally solid, can be considered as an interesting candidate for usage as solid‐state electrolytes in Lithium batteries. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 2065–2071, 2010 相似文献
1000.
Kaolin-filled polypropylene (PP) composites with various kaolin content, processing temperature and shear histories were compounded
using a heated two roll-mill. Prior to thermal analysis, the samples were subjected to extrusion process via capillary rheometer.
The influences of kaolin content, processing temperature and shear stress on crystallization of all samples, including isothermal
and nonisothermal crystallization behaviour were investigated by differential scanning calorimetry (DSC). The results showed
that the increasing kaolin content, processing temperature and shear stress have shifted the crystallization exothermic peak
to higher temperature and reduced the overall crystallization time. 相似文献