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191.
192.
Zahra Khoubi-Arani Seyed Reza Ghaffarian Gity Mir Mohamad Sadeghi 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(2):180-188
Flexible elastomeric polyurethane (EPU) films were synthesized by ultraviolet (UV) curing of thermoplastic polyurethanes (TPUs) through the reaction among poly (oxytetramethylene) diol (PTMO), isophorone diisocyanate (IPDI), cis-2-butene-1,4-diol (cis-BDO), and 1,6-hexanediol diacrylate (HDDA). In order to improve elasticity and structural permanency in the synthesized TPUs, cross-linking reaction involving unsaturated groups of chain extender (cis-BDO) and reactive diluent (HDDA) using 27 and 41 seconds of UV radiation is introduced. Investigation of structure and mechanical properties was performed using FTIR, GPC, and tensile tests. Stress-strain behavior showed that Young's moduli of EPUs were in the range of 0.2 to 0.4 MPa, which is evidence for high flexibility. Three times of repeated loading on one sample up to 100% strain with 10 min intervals for its recovery showed that considerable structural change didn't occur under these conditions and all observed permanent sets vanished within a time not exceeding 10 min. 相似文献
193.
H. Rahbar M. R. Pahlavani J. Sadeghi H. Moayyeri 《International Journal of Theoretical Physics》2009,48(7):2072-2080
In this paper we discuss the one-dimensional non-linear harmonic oscillator and isotropic oscillator in positive curvature.
We will see that in the special case two different oscillator have a same behavior. Finally, by using the parasupersymmetry
algebra we obtain the partner potential and superpotential. These superpotential lead us to obtain the corresponding superchares. 相似文献
194.
Assrary M. Sadeghi J. Zomorrodian M. E. 《International Journal of Theoretical Physics》2021,60(9):3254-3270
International Journal of Theoretical Physics - It has been shown that AdS/CFT correspondence may be realized between some AdS-like cosmological space and CFT living on the boundary. By extending... 相似文献
195.
Nashmil Karimian Pegah Hashemi Abbas Afkhami Hasan Bagheri 《Current Opinion in Electrochemistry》2019
The present study reports the wireless technique that generates asymmetric reactivity on the surface of the conducting substrate without any direct electrical connection in the electrolyte solution by inducing external power. In recent years, bipolar electrochemical systems have received special attention that they are used for new kinds of electrochemical applications ranging from electrodeposition to electroanalytical chemistry. Bipolar electrochemistry is a unique technique because of the lack of direct electrical connection to the bipolar electrode. In this perspective article, we first illustrate the concept and history of the bipolar electrochemistry as well as their application based on the open and closed bipolar configuration in different fields. 相似文献
196.
Structural Chemistry - In the present work, the adenine–cytosine mismatch is theoretically investigated in quaternary systems involving DNA bases. The calculations, in gas phase, are... 相似文献
197.
Omid Bagheri Faranak Sadegh Majid Moghadam Shahram Tangestaninejad Valiollah Mirkhani Iraj Mohammadpoor‐Baltork Mahsa Safiri 《应用有机金属化学》2014,28(5):337-346
The tetrakis(4‐N‐methylpyridinium)porphyrinatopalladium(II) iodide, [Pd(TMPyP)]I4, supported on Dowex 50WX8 and Amberlite IR‐120 ion‐exchange resins, was used as heterogeneous, recyclable and active catalyst for the Suzuki–Miyaura and Heck cross‐coupling reactions. These catalysts were applied to coupling of various aryl halides with phenylboronic acid and styrene in Suzuki and Heck reactions, respectively, and the corresponding products were obtained in excellent yields and short reaction times. The catalysts could be recovered easily by simple filtration and reused several times without significant loss of their catalytic activity. The catalysts were characterized by diffuse‐reflectance UV–visible spectroscopy and scanning electron microscopy, and their stability was confirmed by TGA. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
198.
Bahram Sadeghi Bigham Marzieh Eskandari Maryam Tahmasbi 《Journal of computational science》2012,3(3):127-131
The polar diagram of a set of points in a plane and its extracted dual EDPD were recently introduced for static and dynamic cases. In this paper, the near-pole polar diagram NPPD for a set of points is presented. This new diagram can be considered as a generalization of the polar diagram and has applications in several communication systems and robotics problems. After reviewing the NPPD of points, we solve the problem for a set of line segments and simple polygons in optimal time Θ(n log n), where n is the number of line segments or polygon vertices. We introduce duality for the NPPD of points and identify some applications. 相似文献
199.
DC electrorheological response of polyethylene/organically modified layered silicate nanocomposites
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Soheil Sadeghi Mohammad Arjmand Tieqi Li Uttandaraman Sundararaj 《Journal of Polymer Science.Polymer Physics》2017,55(17):1298-1309
The present work reports the electrorheological (ER) response of high‐density polyethylene (HDPE)/organically modified silicate layers nanocomposites based on four commercially available HDPE matrices. Two single‐site catalyzed bimodal resins, one single‐site catalyzed unimodal resin and one Ziegler–Natta catalyzed unimodal resin are studied. It is revealed that the distinct separation of the two modes of the bimodal HDPE resins significantly enhances the ER response. It is proposed that the slower structural relaxation modes introduced by higher molecular weight species in the bimodal HDPE matrices enhance the ER response of the nanocomposites. This is ascribed to the longer induction time for leaking current density, which is an indicator of mobility and release of immobilized cationic surfactants at the silicate layers surface induced by field exposure. It is found that the screening effect of prematurely released cationic surfactants leads to a weaker ER response in nanocomposites whose matrices have faster relaxation modes. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017 , 55, 1298–1309 相似文献
200.
Research on Chemical Intermediates - A novel six-coordinate complex of Zr(IV) with curcumin ligand was synthesized and characterized by thermogravimetric analysis, elemental analysis and... 相似文献