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91.
Jihene Lagha Faouzi Triki Habib Zribi 《Mathematical Methods in the Applied Sciences》2017,40(10):3608-3636
We consider the Lamé system for an elastic medium consisting of an inclusion embedded in a homogeneous background medium. Based on the field expansion method and layer potential techniques, we rigorously derived the asymptotic expansion of the perturbed displacement field because of small perturbations in the interface of the inclusion. We extend these techniques to determine a relationship between traction‐displacement measurements and the shape of the object and derive an asymptotic expansion for the perturbation in the elastic moment tensors because of the presence of small changes in the interface of the inclusion. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
92.
A new helically chiral hexacyclic phosphine, containing one thiophene ring was prepared in good yield via a five-step sequence involving a palladium-catalysed Mizoroki-Heck coupling reaction and classical oxidative photocyclisation. A mononuclear air stable ruthenium complex of this phosphine was also prepared and characterised. 相似文献
93.
Fatimah Mohammed Alzahrani Norah Salem Alsaiari Khadijah Mohammedsaleh Katubi Abdelfattah Amari Abubakr M. Elkhaleefa Faouzi Ben Rebah Mohamed A. Tahoon 《Molecules (Basel, Switzerland)》2021,26(16)
We report in the present study the in situ formation of magnetic nanoparticles (Fe3O4 or Fe) within porous N-doped carbon (Fe3O4/N@C) via simple impregnation, polymerization, and calcination sequentially. The synthesized nanocomposite structural properties were investigated using different techniques showing its good construction. The formed nanocomposite showed a saturation magnetization (Ms) of 23.0 emu g−1 due to the implanted magnetic nanoparticles and high surface area from the porous N-doped carbon. The nanocomposite was formed as graphite-type layers. The well-synthesized nanocomposite showed a high adsorption affinity toward Pb2+ toxic ions. The nanosorbent showed a maximum adsorption capacity of 250.0 mg/g toward the Pb2+ metallic ions at pH of 5.5, initial Pb2+ concentration of 180.0 mg/L, and room temperature. Due to its superparamagnetic characteristics, an external magnet was used for the fast separation of the nanocomposite. This enabled the study of the nanocomposite reusability toward Pb2+ ions, showing good chemical stability even after six cycles. Subsequently, Fe3O4/N@C nanocomposite was shown to have excellent efficiency for the removal of toxic Pb2+ ions from water. 相似文献
94.
Optical Review - Multimode fibers (MMF) are enjoying a renewed attention boosted by recent advances in multimode complex nonlinear optics. Reason behind nonlinearity is occurred either due to... 相似文献
95.
The crown ethers dibenzo-16-crown-4 and dibenzo-18-crown-5 and a diaryl polyether were complexed by the chromium tricarbonyl group for the purpose of selective functionalization. This complexation did indeed permit exclusive functionalization of the complexed ring. CHO and CH2OH functionalities were introduced ortho to the ether group. It was noted that the nature of the two ether chains had a strong influence on the regioselectivity of the functionalization, which occurred preferentially on the side with the polyether chain. Photochemical decomplexation produced functionalized organic crown ethers. 相似文献
96.
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98.
Rania Charrad Dr. Hanna E. Solt Dr. József Valyon László Trif Dr. Faouzi Ayari Dr. Mourad Mhamdi Jenő Hancsók Dr. Ferenc Lónyi 《ChemistryOpen》2020,9(11):1123-1134
Co/SSZ-13 zeolites were prepared by heating the finely dispersed mixture of NH4-SSZ-13 and different cobalt salts up to 550 °C. Investigations by thermogravimetry – differential scanning calorimetry – mass spectrometry provided new insight into details of the solid-state reaction. Formation of Co carrying hydrate melt or volatile species was shown to proceed from chloride, nitrate, or acetylacetonate Co precursor salts upon thermal treatment. This phase change allows the transport of the Co species into the zeolite pores. The reaction of the NH4+ or H+ zeolite cations and the mobile Co precursors generates vapor or gas products, readily leaving the zeolite pores, and cobalt ions in lattice positions suggesting that solid-state ion-exchange is the prevailing process. The obtained catalysts are of good activity and N2 selectivity in the CH4/NO-SCR reaction. The thermal treatment of acetate or formate salts give solid intermediates that are unable to get in contact and react with the cations in the zeolite micropores. These catalysts contain mainly Co-oxide clusters located on the outer surface of the zeolite crystallites and have poor catalytic performance. 相似文献
99.
A new helically chiral hexacyclic system, bearing an acetoxymethyl group, was prepared from a simple naphthalene building block in good yield and purity, via a four-step sequence involving palladium-catalysed Heck couplings and oxidative photocyclizations. Suitable crystals of the latter indicate that its conformation closely resembles that of unsubstituted [6]helicene, whose idealized symmetry is C2. The optical properties of the hexacyclic helicene were investigated and show interesting behaviour. 相似文献
100.
Abderrahmen Guesmi Mohamed Faouzi Zid Ahmed Driss 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):511-512
In the title compound, disodium cobalt tetrakis(dihydrogenphosphate) tetrahydrate, the CoII ion lies on an inversion centre and is octahedrally surrounded by two water molecules and four H2PO4 groups to give a cobalt complex anion of the form [Co(H2PO4)4(OH2)]2?. The three‐dimensional framework results from hydrogen bonding between the anions. The relationship with the structures of Co(H2PO4)2·2H2O and K2CoP4O12·5H2O is discussed. 相似文献