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排序方式: 共有148条查询结果,搜索用时 31 毫秒
1.
Wakif Abderrahim Chamkha Ali Thumma Thirupathi Animasaun I. L. Sehaqui Rachid 《Journal of Thermal Analysis and Calorimetry》2021,143(2):1201-1220
Journal of Thermal Analysis and Calorimetry - Sequel to the fact that hybrid nanofluidic systems (e.g. scalable micro-/nanofluidic device) exhibit greater thermal resistance with increasing... 相似文献
2.
Two difference schemes are derived for numerically solving the one-dimensional time distributed-order fractional wave equations. It is proved that the schemes are unconditionally stable and convergent in the \(L^{\infty }\) norm with the convergence orders O(τ 2 + h 2+Δγ 2) and O(τ 2 + h 4+Δγ 4), respectively, where τ,h, and Δγ are the step sizes in time, space, and distributed order. A numerical example is implemented to confirm the theoretical results. 相似文献
3.
Tanguy Jousselin-Oba Masashi Mamada Karen Wright Jrome Marrot Chihaya Adachi Abderrahim Yassar Michel Frigoli 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2022,134(1):e202112794
We report the synthesis and optoelectronic properties of TIPS-peri-pentacenopentacene ( TIPS-PPP ), a vertical extension of TIPS-pentacene ( TIPS-PEN ) and a low-band-gap material with remarkable stability. We found the synthetic conditions to avoid the competition between 1,2- and 1,4-addition of lithium acetylide on the large aromatic dione. The high stability of TIPS-PPP is due to the peri-fusion which increases the aromaticity by generating two localized aromatic sextets that are flanked with 2 diene fragments, similar to two fused-anthracenes. Like TIPS-PEN , TIPS-PPP shows the archetypal 2D brickwall motif in crystals with a larger transfer integral and smaller reorganization energy. The high mobility of up to 1 cm2 V?1 s?1 was obtained in an organic field-effect transistor fabricated by a wet process. Also, TIPS-PPP was used as a near-infrared (NIR) emitter for NIR organic-light-emitting-diode devices resulting in a high external quantum efficiency at 800 nm. 相似文献
4.
Raoudha Abderrahim 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):581-585
The reaction of ethyl chloroformate with iminoesters derived from 3-aminotriazole, followed by amine or phenyl hydrazine condensation, leads to a variety of 1,2,4-triazolo-1,3,5-triazin-4-ones in a 60–85% overall yield. 相似文献
5.
Tanguy Jousselin-Oba Masashi Mamada Atsushi Okazawa Jrome Marrot Takayuki Ishida Chihaya Adachi Abderrahim Yassar Michel Frigoli 《Chemical science》2020,11(44):12194
Biradicaloid compounds with an open-shell ground state have been the subject of intense research in the past decade. Although diindenoacenes are one of the most developed families, only a few examples have been reported as active layers in organic field-effect transistors (OFETs) with a charge mobility of around 10−3 cm2 V−1 s−1 due to a steric disadvantage of the mesityl group to kinetically stabilize compounds. Herein, we disclose our efforts to improve the charge transport of the diindenoacene family based on hexahydro-diindenopyrene (HDIP) derivatives with different annelation modes for which the most reactive position has been functionalized with (triisopropylsilyl)ethynyl (TIPS) groups. All the HDIP derivatives show remarkably higher stability than that of TIPS-pentacene, enduring for 2 days to more than 30 days, which depends on the oxidation potential, the contribution of the singlet biradical form in the ground state and the annelation mode. The annelation mode affects not only the band gap and the biradical character (y0) but also the value of the singlet–triplet energy gap (ΔES–T) that does not follow the reverse trend of y0. A method based on comparison between experimental and theoretical bond lengths has been disclosed to estimate y0 and shows that y0 computed at the projected unrestricted Hartree–Fock (PUHF) level is the most relevant among those reported by all other methods. Thanks to their high stability, thin-film OFETs were successfully fabricated. Well balanced ambipolar transport was obtained in the order of 10−3 cm2 V−1 s−1 in the bottom-gate/top-contact configuration, and unipolar transport in the top-gate/bottom-contact configuration was obtained in the order of 10−1 cm2 V−1 s−1 which is the highest value obtained for biradical compounds with a diindenoacene skeleton.Biradicaloid HDIP derivatives show that the ΔES–T gap does not follow the reverse trend of the biradical character but depends more on the delocalization of the radical centres at the outer rings. 相似文献
6.
Abderrahim Jourani Emilio Vilches 《Journal of Optimization Theory and Applications》2017,173(1):91-116
The existence and the convergence (up to a subsequence) of the Moreau-Yosida regularization for the state-dependent sweeping process with nonregular (subsmooth and positively alpha-far) sets are established. Then, by a reparametrization technique, the existence of solutions for bounded variation continuous state-dependent sweeping processes with nonregular (subsmooth and positively alpha-far) sets is proved. An application to vector hysteresis is discussed, where it is shown that the Play operator with positively alpha-far sets is well defined for bounded variation continuous inputs. 相似文献
7.
Begaa Samir Messaoudi Mohammed Ouanezar Abdelkader Hamidatou Lylia Malki Abderrahim 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(2):1107-1112
Journal of Radioanalytical and Nuclear Chemistry - The objectives of this research were to study the elemental concentrations of Mentha spicata L., using a sensitive nuclear analytical technique... 相似文献
8.
Reaction of ethyl chloroformate and acyl chlorides with iminoesters derived from 2- aminobenzimidazole, followed by Grignard reagent condensation leads to a variety of oxadiazinobenzimidazoles in good yield. 相似文献
9.
Raoudha Abderrahim Belgacem Baccar et Mohamed Lamine Benkhoud 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):1033-1040
The reaction of hexamethylphosphotriamide or methylphosphonic bis(dimethylamide) compounds with amidines derived from N-Benzimidazoyl imidates 1 leads to (1,2a)benzimidazolo-1,3,5,2-tiazaphosphorine-2-oxides 4 in good yields. If the condensation is realized at room temperature, N-phosphonic amidines 3 can be isolated as intermediates. The isolated compounds 2 , 3 , and 4 are identified by spectroscopic methods: IR, 1 H, 13 C, 31 P, NMR, and M.S. 相似文献
10.
In this Note, a numerical investigation of laminar convection wake above a heated plate placed in a channel is carried out. An analytical study based on a three region structure is proposed in the immediate neighbourhood of the trailing edge. Velocity and temperature at the centerline channel as well as the pressure gradient are presented in asymptotic expressions. Comparison of these results with numerical solutions enhances the analytical study. To cite this article: Z. Doulfoukar, A. Achiq, C. R. Mecanique 333 (2005). 相似文献