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Fouad Laoutid Marion Lorgouilloux Didier Lesueur Leila Bonnaud Philippe Dubois 《Polymer Degradation and Stability》2013
In this study, we evaluated the potential flame retardant effect of calcium-based hydrated minerals, such as hydrated lime, partially and completely hydrated dolomitic limes in polyethylene (MDPE) and ethylene vinyl acetate copolymers (EVA) and compared to that obtained with magnesium di-hydroxide (MDH). The most significant flame retardant effects, observed using the mass loss calorimeter test, indicated that Ca-based MDPE composites showed similar peak Heat Release Rate (pHRR) level to that obtained with MDH composite while the pHRR was lower for Ca-based fillers in EVA compositions. X-ray Diffraction (XRD) data, combined with thermal analysis results, indicated that the calcium di-hydroxide plays a role in the formation of an intumescent cohesive residue during the combustion. Indeed, Ca(OH)2 reacts with CO2 formed during the thermal degradation of the polymer to generate CaCO3 (calcium carbonate) that contributes to the enhancement of the mechanical resistance of the residue. 相似文献
13.
Saeed Bahadorikhalili Samira Ansari Haleh Hamedifar Leila Ma'mani Mohsen Babaei Rahim Eqra Mohammad Mahdavi 《应用有机金属化学》2019,33(4)
In this paper, a novel catalyst is introduced based on the immobilization of palladium on modified magnetic graphene oxide nanoparticles. The catalyst is characterized by several methods, including transmission electron microscopy, scanning electron microscopy, X‐ray fluorescence, vibrating‐sample magnetometer, Fourier transform‐infrared and dynamic light scattering (DLS) analysis. The activity of the catalyst was investigated in the synthesis of 4(3H)‐quinazolinones via Pd‐catalyzed carbonylation‐cyclization of N‐(2‐bromoaryl) benzimidamides by Mo (CO)6. The Mo (CO)6 is used as a carbon monoxide source for performing the reaction under mild conditions. The catalyst showed good reusability, and no change in activity was observed after 10 cycles of recovery. 相似文献
14.
Smailii Parisa Pakroo Raziye Mohammadkhani Ramin Jafarian Vahab Kabiri Esfahani Farhad Hassani Leila 《Journal of the Iranian Chemical Society》2020,17(1):127-134
Journal of the Iranian Chemical Society - Herein, we investigated the interaction of cisplatin loaded on GO (GO@CDDP) with two regulatory sequences, BRCA1 and BRCA2, synthesized from ssDNA based on... 相似文献
15.
Rahim Hekmat Shoar Majid M. Heravi Leila Pedram Shadi Hasan Raeiat Zeinab Jaddi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2563-2567
A facile and rapid synthesis of thio compounds, analogues to ciprofloxacin, and norfloxacin is described. 相似文献
16.
Leila Irannejad Seyed Javad Ahmadi Sodeh Sadjadi Mojtaba Shamsipur 《Journal of the Iranian Chemical Society》2018,15(1):111-119
Metal-free electrocatalysts for oxygen reduction reaction (ORR) are key to the development of efficient, durable, and low-cost alternatives to noble-metal-based electrocatalysts in fuel cell cathodes. In recent years, many efforts are directed to the metal-free catalyst based on heteroatom-doped graphene. In this work, we demonstrate that the graphene surface can be converted into the catalyst for the oxygen reduction by chemical functionalization. In this context, we first synthesized malononitrile-functionalized graphene oxide. Amidoximation of nitrile group and reduction in graphene oxide were then carried out by hydroxylamine in one step. The electrochemical behavior of functionalized graphene-modified electrode for the reduction in oxygen was studied. The results showed that the electrocatalyst fabricated by this method exhibited striking catalytic activities in alkaline solution. In alkaline solution, this catalyst showed a competitive activity to the commercial Pt catalyst via four-electron transfer pathway with better ORR selectivity and stability. In addition, this metal-free electrocatalyst exhibited tolerance to methanol crossover effect. Based on its outstanding performance, this functionalized graphene electrocatalyst showed the promising prospect of a metal-free catalyst for fuel cell with much lower cost than currently used Pt/C catalyst. 相似文献
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Leila S. Boulos Ewies F. Ewies Amin F. M. Fahmy Maysa E. Mohram 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):790-803
Abstract The reaction of 5(4H)-pyrazolone with phosphorus ylides afforded new triphenylphosphanylidene alkanone derivatives. Moreover, its benzylidene derivative reacted with Wittig–Horner reagents to give the corresponding dialkoxyphosphoryl, alkyl phosphonate, and heterocyclic products. Treatment of pyrazole-4-carbaldehyde with Wittig–Horner reagents and trialkyl phosphites gave the respective alkyl phosphonate adducts. Mechanisms accounting for the formation of the new products are discussed. The biological activity of some of the newly synthesized compounds was also examined. 相似文献
19.
Ali Reza Mahdavian Mahdi Abdollahi Leila Mokhtabad Farshid Ziaee 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(10):1583-1596
Many reports exist in the literature about the application of 1H and 13C‐NMR techniques to analyze the copolymer structure and composition and also determination of reactivity ratios. In this work, on‐line 1H‐NMR spectroscopy has been applied to identify reactivity ratios of itaconic acid and acrylonitrile in the solution phase (DMSO as the solvent) and in the presence of AIBN as the radical initiator. All the peaks corresponding to the existing protons were assigned quietly. Therefore, the kinetics of the copolymerization reaction was investigated by studying the variation of integral of two characteristic peaks regarding each monomer. The obtained data were used to find the reactivity ratios of acrylonitrile and itaconic acid by linear least‐squares methods such as Finemann‐Ross, inverted Finemann‐Ross, Mayo‐Lewis, Kelen‐Tudos, extended Kelen‐Tudos and Mao‐Huglin. In addition, a non‐linear least‐square method (Tidwell‐ Mortimer) was used at low conversions. Extended Kelen‐ Tudos and Mao‐Huglin were applied to determine reactivity ratio values at high conversions as well. 相似文献
20.
Kazem D. Safa Aynaz Feyzi Maryam Allahvirdinesbat Leila Sarchami Parvaneh Nakhostin Panahi 《合成通讯》2013,43(3):382-390
An efficient four-component synthesis of 1,2,4,5-tetrasubstituted imidazoles is described by one-step condensation of an aldehyde, benzil, ammonium acetate, and primary aromatic amine with nanostructure Fe-Cu/ZSM-5 bimetallic oxides in water under ultrasonic irradiation. The short reaction time, good yields, environmental friendly procedure, mild reaction conditions, and convenient operation are important advantage of this protocol. The products generated during the study have been utilized as substrates for synthesis of organosilicon-containing imidazoles. Synthesis of tris(triorganosilyl)methylimidazole derivatives were carried out using organolithium reagent (Me3Si)3CLi, prepared via metalation of (Me3Si)3CH with methyllithium in tetrahydrofuran, in excellent yields. 相似文献