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排序方式: 共有190条查询结果,搜索用时 312 毫秒
41.
Mustapha Aitali Larbi El Firdoussi Abdellah Karim Alejandro F. Barrero Miguel Quirs 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(9):1088-1089
The title compound, [(S)‐2‐(anilinomethyl)pyrrolidine‐N,N′]‐chloro(η6‐para‐cymene)ruthenium(II) chloride, [RuCl‐(C10H14)(C11H16N2)]Cl, has been synthesized by the reaction of [RuCl2(p‐cymene)]2 (p‐cymene is para‐isopropyltoluene) with (S)‐2‐(anilinomethyl)pyrrolidine in triethylamine/2‐propanol. The Ru atom is in a pseudo‐tetrahedral environment coordinated by a chloride ligand, the aromatic hydrocarbon is linked in a η6 manner and the amine is linked via its two N atoms. The chloride anion is involved in hydrogen bonding with the diamine moieties through N—H?Cl interactions, with N?Cl distances of 3.273 (4) and 3.352 (4) Å. 相似文献
42.
Synergistic Effect of Bioactive Monoterpenes against the Mosquito,Culex pipiens (Diptera: Culicidae)
Amal Ramzi Abdelhakim El Ouali Lalami Saoussan Annemer Yassine Ez zoubi Amine Assouguem Mikhlid H. Almutairi Mohamed Kamel Ilaria Peluso Sezai Ercisli Abdellah Farah 《Molecules (Basel, Switzerland)》2022,27(13)
Mosquitoes represent one of the most important vectors and are responsible for the transmission of many arboviruses that affect human and animal health. The chemical method using synthetic insecticides disturbs the environmental system and promotes the appearance of resistant insect species. Therefore, this study investigated the insecticidal effect of some binary monoterpene combinations (1,8 cineole + α-pinene and carvone + R (+)-pulegone) using a mixture design approach. The fumigant toxicity was evaluated against Culex pipiens female adults using glass jars. The results show that the toxicity varies according to the proportions of each compound. Indeed, Mixture 1 (1,8-cineole + α-pinene) displayed a strong toxic effect (51.00 ± 0.86% after 24 h and 100.00 ± 0.70% after 48 h) when the pure compounds were tested at 0.25/0.75 proportions of 1,8-cineole and α-pinene, respectively. Nevertheless, the equal proportion (0.5/0.5) of carvone and R (+)-pulegone in Mixture 2 exhibited a toxic effect of 54.35 ± 0.75% after 24 h and 89.96 ± 0.14% after 48 h, respectively. For Mixture 1, the maximum area of mortality that the proposed model indicated was obtained between 0/1 and 0.25/0.75, while the maximum area of mortality in the case of Mixture 2 was obtained between 0.25/0.75 and 0.75/0.25. Moreover, the maximum possible values of mortality that could be achieved by the validated model were found to be 51.44% (after 24 h) and 100.24% (after 48 h) for Mixture 1 and 54.67% (after 24 h) and 89.99% (after 48 h) for Mixture 2. It can be said that all purev molecules tested through the binary mixtures acted together, which enhanced the insecticide’s effectiveness. These findings are very promising, as the chemical insecticide (deltamethrin) killed only 19.29 ± 0.01% and 34.05 ± 1.01% of the female adults after 24 h and 48 h, respectively. Thus, the findings of our research could help with the development of botanical insecticides that might contribute to management programs for controlling vectors of important diseases. 相似文献
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44.
Optimization Letters - By reviewing the Logarithmic–quadratic proximal (LQP) method, in this paper we suggest and analyze a new LQP alternating direction scheme for the separable constrained... 相似文献
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47.
Abdellah Bnouhachem 《Journal of Mathematical Analysis and Applications》2006,314(2):513-525
In this paper, we presented a new projection and contraction method for linear variational inequalities, which can be regarded as an extension of He's method. The proposed method includes several new methods as special cases. We used a self-adaptive technique to adjust parameter β at each iteration. This method is simple, the global convergence is proved under the same assumptions as He's method. Some preliminary computational results are given to illustrate the efficiency of the proposed method. 相似文献
48.
Michel Boulouard Sylvain Rault Patrick Dallemagne Abdellah Alsaïdi Max Robba 《Journal of heterocyclic chemistry》1996,33(1):87-91
Treatment of 2-(2-formyl-1H-pyrrol-1-yl)-3-thiophenecarbonitrile by sodium percarbonate afforded, in a one-pot sequence and on a multigram scale, 5,6-dihydro-6-hydroxy-4H-pyrrolo[1,2-a]thieno-[3,2-f][1,4]diazepin-4-one whose reactivity towards various nucleophiles like amines, hydrazines and thiols was evaluated. 相似文献
49.
Abdellah Ech-Chahad 《Tetrahedron letters》2005,46(31):5113-5115
Capitalizing on in situ activation with the cyclic phosphonic anhydride PPAA (1), the conversion of carboxylic acids into hydroxamic acids has been reduced to an experimentally simple one-pot operation that addresses the issue of polyacylation without resorting to a large excess of hydroxylamine or to protection. Scope and selectivity were satisfactory with a wide range of substrates, including α,β-unsaturated acids and hydroxyacids. 相似文献
50.
The Douglas–Peaceman–Rachford–Varga operator splitting methods (DPRV methods) are attractive methods for monotone variational
inequalities. He et al. [Numer. Math. 94, 715–737 (2003)] proposed an inexact self-adaptive operator splitting method based on DPRV. This paper relaxes the inexactness
restriction further. And numerical experiments indicate the improvement of this relaxation.
相似文献