排序方式: 共有74条查询结果,搜索用时 62 毫秒
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Sana Zama Abdelmalek Bouraiou Sofiane Bouacida Thierry Roisnel Ali Belfaitah 《Tetrahedron letters》2013
A new class of thiazolo[3,2-a]imidazole derivatives is obtained in good yields, by reacting 1-methyl-2-bromoimidazolium salts bearing N+-CH2COAr, N+-CH2COMe, N+-CH2COOMe, or N+-CH2CN fragments, with carbon disulfide in the presence of Et3N at room temperature. The mesoionic structures of these compounds are established by NMR spectroscopy and by single-crystal X-ray analysis. 相似文献
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Rafika Bouchene Sofiane Bouacida Fadila Berrah Thierry Roisnel 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(7):672-676
In the title cadmium chloride salt, (C3H5N4O2)4[CdCl6]·4H2O, the asymmetric unit comprises two N‐protonated 5‐amino‐3‐carboxy‐4H‐1,2,4‐triazol‐1‐ium cations, half a [CdCl6]4− anion and two molecules of water. The Cd2+ cation is located on a centre of inversion and is coordinated by six chloride anions, forming a distorted octahedron. In the crystal structure, alternating layers of cations and anions are arranged along the [101] direction, forming a three‐dimensional supramolecular network via a combination of hydrogen‐bonding and aromatic stacking interactions. 相似文献
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Poly(vinylalcohol)/poly(ethyleneglycol)/poly(ethyleneimine) blend membranes were prepared by solution casting followed by
solvent evaporation. The chemical structure of the prepared membranes was analyzed by FTIR and DSC. The sorption behavior
as well as the permeabilities of the membranes for pure CO2 and N2 were investigated. The results show that the PVA/PEI/PEG membranes possess a higher permeability of CO2 and a lower permeability of N2. The membrane displays a CO2 permeability of 27 Barrer, and a N2 permeability of 3 Barrer at 25°C and 1 bar. CO2 sorption behavior of the composite membrane, which can be classified as a dual-mode sorption model, and N2 sorption behavior of the copolymeric membrane is in agreement with the Fickian diffusion model.
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Bouzina Abdeslem Berredjem Malika Belhani Billel Bouacida Sofiane Marminon Christelle Le Borgne Marc Bouaziz Zouhair Aissaoui Mohamed 《Research on Chemical Intermediates》2021,47(4):1359-1376
Research on Chemical Intermediates - We demonstrate here a rapid and comfortable synthetic sequence to benzothiadiazinone dioxide (six-membered cyclic sulfamide) derivatives, analogues of... 相似文献
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Sofiane Ramdani Frédéric BoucharaOlivier Caron 《Nonlinear Analysis: Real World Applications》2012,13(4):1891-1903
We numerically investigate the ability of a statistic to detect determinism in time series generated by high-dimensional continuous chaotic systems. This recently introduced statistic (denoted VE2) is derived from the averaged false nearest neighbors method for analyzing data. Using surrogate data tests, we show that the proposed statistic is able to discriminate high-dimensional chaotic data from their stochastic counterparts. By analyzing the effect of the length of the available data, we show that the proposed criterion is efficient for relatively short time series. Finally, we apply the method to real-world data from biomechanics, namely postural sway time series. In this case, the results led us to exclude the hypothesis of nonlinear deterministic underlying dynamics for the observed phenomena. 相似文献
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In testing cancellous bone using ultrasound, two types of longitudinal Biot’s waves are observed in the received signal. These are known as fast and slow waves and their appearance depend on the alignment of bone trabeculae in the propagation path and the thickness of the specimen under test (SUT). They can be used as an effective tool for the diagnosis of osteoporosis because wave propagation behavior depends on the bone structure. However, the identification of these waves in the received signal can be difficult to achieve.In this study, ultrasonic wave propagation in a 4 mm thick bovine cancellous bone in the direction parallel to the trabecular alignment is considered. The observed Biot’s fast and slow longitudinal waves are superimposed; which makes it difficult to extract any information from the received signal. These two waves can be separated using the space alternating generalized expectation maximization (SAGE) algorithm. The latter has been used mainly in speech processing.In this new approach, parameters such as, arrival time, center frequency, bandwidth, amplitude, phase and velocity of each wave are estimated. The B-Scan images and its associated A-scans obtained through simulations using Biot’s finite-difference time-domain (FDTD) method are validated experimentally using a thin bone sample obtained from the femoral-head of a 30 months old bovine. 相似文献
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Potentiometric biosensors based on butyrylcholinesterase are developed by co-reticulation of the enzyme with glutaraldehyde on an electropolymerized polyethyleneimine film at the electrode surface. The BuChE-electrode was tested as biochemical sensor for detection of an organophosphorus pesticide, trichlorfon in liquid, the detection being based on the enzyme inhibition. The enzyme electrode showed a detection limit for trichlorfon below 10−7 M. 相似文献