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991.
Nabendu B. Pramanik Dibyendu S. Bag Sarfaraz Alam Golok B. Nando Nikhil K. Singha 《Journal of polymer science. Part A, Polymer chemistry》2013,51(16):3365-3374
This investigation reports the preparation and characterization of thermally amendable functional polymer bearing furfuryl functionality via reversible‐addition fragmentation and chain transfer (RAFT) polymerization and Diels‐Alder (DA) reaction. In this case, furfuryl methacrylate (FMA) was polymerized using 4‐cyano‐4‐[(dodecylsulfanylthiocarbonyl)sulfanyl] pentanoic acid as RAFT reagent and 4,4′‐azobis(4‐cyanovaleric acid) as thermal initiator. 1H NMR, 13C NMR, and matrix‐assisted laser desorption ionization time‐of‐flight mass spectrometry analysis showed that furfuryl group in poly(furfuryl methacrylate) (PFMA) was not affected during RAFT polymerization and the tailor‐made polymer had RAFT end group. The DA reaction was successfully carried out between the reactive furfuryl functionality of PFMA and different bismaleimides. The thermoreversible property of these DA polymers was characterized by FT‐IR and DSC analysis. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013 , 51, 3365–3374 相似文献
992.
Computational fluid dynamics (CFD) is used extensively by engineers to model and analyze complex issues related to hydraulic design, planning studies for future generating stations, civil maintenance and supply efficiency. In order to find the optimal position of a baffle in a rectangular primary sedimentation tank, computational investigations are performed. Also laboratory experiments are conducted to verify the numerical results and the measured velocity fields which were by Acoustic Doppler Velocimeter (ADV) are used. The GMRES algorithm as a pressure solver was used in the computational modeling. The results of computational investigations performed in the present study indicate that the favorable flow field (uniform in the settling zone) would be enhanced for the case that the baffle position provide small circulation regions volume and dissipate the kinetic energy in the tank. Also results show that the GMRES algorithm can obtain the good agreement between the results of numerical models and experimental tests. 相似文献
993.
Shaheen M. Sarkar Md. Nazmul Alam Md. Rezwan Miah 《Reaction Kinetics and Catalysis Letters》2009,96(1):175-183
A palladium (Pd) catalyst was prepared by immobilization of a 1,2-diaminocyclohexane based Pd-complex onto amorphous silica
gel and its applications as a heterogeneous catalyst for Suzuki-Miyaura and Sonogashira coupling reactions are described.
The catalyst was highly efficient, reusable and air-stable.
An erratum to this article is available at . 相似文献
994.
Kamruzzaman Khan M. Ali Akbar Md. Nur Alam 《Journal of the Egyptian Mathematical Society》2013,21(3):233-240
In this paper, the modified simple equation (MSE) method is implemented to find the exact solutions for the nonlinear Drinfel’d–Sokolov–Wilson (DSW) equation and the modified Benjamin–Bona–Mahony (mBBM) equations. The efficiency of this method for constructing these exact solutions has been demonstrated. It is shown that the MSE method is direct, effective and can be used for many other nonlinear evolution equations (NLEEs) in mathematical physics. Moreover, this technique reduces the large volume of calculations. 相似文献
995.
Tetrabutylammonium tribromide (TBATB) has been found to be an efficient catalyst for the one-pot synthesis of highly substituted piperidines through a combination of 1,3-dicarbonyl compounds, aromatic aldehydes, and various amines in ethanol at room temperature. Atom economy, good yields, environmentally benign, and mild reaction conditions are some of the important features of this protocol. 相似文献
996.
997.
Nisha SoodBiswas Md Asraful Sekh Samir Sarkar Amitabha Basuray 《Optics Communications》2012,285(10-11):2607-2610
In this short communication we are reporting a new kind of rod lens with toric power with moderately large power difference. These rods can be directly used in coupling power from a semiconductor laser to optical fiber or in free space communication to convert the beam shape. This rod may directly be butt-jointed to the laser, which may attract many application scientists. Moreover, anamorphic power in a GRIN lens can be generated by proper selection of geometry of the substrate for ion exchange. This may lead to a new kind of optical system that needs further exploration. 相似文献
998.
Obliquely propagating altra-low-frequency dust-electromagnetic waves in a self-gravitating, warm, magnetized, two fluid dusty
plasma system have been investigated. Two special cases, namely, dust-Alfvén mode propagating parallel to the external magnetic
field and dustmagnetosonic mode propagating perpendicular to the external magnetic field have also been considered. It has
been shown that effects of self-gravitational field, dust fluid temperature, and obliqueness significantly modify the dispersion
properties of these ultra-low-frequency dust-electromagnetic modes. It is also found that in parallel propagating dust-Alfvén
mode these effects play no role, but in obliquely propagating dust-Alfvén mode or perpendicular propagating dust-magnetosonic
mode the effect of self-gravitational field plays destabilizing role whereas the effect of dust/ion fluid temperature plays
stabilizing role. 相似文献
999.
Natural rubber (NR) latex was purified through triple centrifugation process and film samples were prepared. The strain-induced crystallization was studied during the uniaxial elongation of the NR samples at room temperature. Crystalline orientation was detected by wide angle x-ray diffraction (WAXD) measuring the intensity of 200 and 120 reflections. The WAXD patterns were compared with the aspect ratio (width/length) of the original NR films. The results indicate that the induced crystals have a biaxial orientation (BO), where the c-axis is parallel to the draw direction and the a-axis is parallel to the film surface. Using the WAXD through patterns, we distinguish the highly oriented BO region in the samples. In order to analyze the structure and properties of the NR, the effect of BO is an essential factor. 相似文献
1000.
1,1-Diaryl moieties are core structures in a wide range of bioactive and pharmaceutical compounds.Transition-metal catalysis is a convenient approach to accessing these invaluable compounds affording high yields and enantioselectivities.This review summarizes 1,1-diarylalkanes synthesis through transition metal catalysis.Particular focus is given to recent developments,such as reductive cross-electrophile couplings,benzylic C–H bond arylation,transformations involving metal migration,asymmetric hydrogenation of 1,1-diarylalkenes and three-component coupling reactions. 相似文献