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21.
Farhad Shirini Manouchehr Mamaghani Seyyed Vahid Atghia 《Journal of the Iranian Chemical Society》2013,10(3):415-420
Nanoporous Na+-montmorillonite sulfonic acid was found to be an efficient and green catalyst for the synthesis of various 14-aryl-14H-dibenzo[a,j]xanthenes and 1,8-dioxo-dodecahydroxanthene derivatives by the reaction of aldehydes with 2-naphthol and 1,3-cyclohexanedione, respectively. This novel synthetic method has the advantages of high yields, short reaction times and recyclability of the catalyst, simplicity and easy workup compared to the conventional methods reported in the literature. 相似文献
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We analytically investigate the effect of an external mirror on the stability of an injected semiconductor laser, the latter treated as injected damped oscillators. In the studied configuration, the injected semiconductor laser with an external mirror is under the influence of a chaotic oscillating optical signal that is generated by a similar semiconductor master laser. We derive our results in terms of the damping rate and resonance frequency. We show that the external mirror can eliminate the unstable modes of the injected laser at low frequencies. Furthermore, the mirror can enhance the damping of the oscillation modes of the injected semiconductor laser; consequently, the driven response of the injected laser may have a broad spectrum, even wider than that of the chaotic driving signal. We also show results for the bandwidths of the injection amplitude and phase increment as functions of the injection rate and feedback strength of the external mirror. In addition, we use bifurcation and time-series curves to describe the dynamical behavior of the injected laser. We identify the feedback strength of injected laser, relative to that of the master laser, which induces synchronization between the injected-laser oscillation modes and the master laser. 相似文献
24.
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
25.
Farhad Shirini Somayeh Akbari-DadamahalehAli Mohammad-Khah 《Comptes Rendus Chimie》2013,16(10):945-955
Rice-husk-supported FeCl3 nano-particles (FeCl3–RiH) were prepared and used as an environmentally friendly catalyst in the synthesis of β-amino carbonyl compounds, 1,8-dioxo-octahydro xanthenes, and bis-indolyl methanes from simple and readily available precursor molecules. 相似文献
26.
In this paper, an electric circuit to control the dynamic output of a semiconductor laser is introduced. The circuit controls chaos and instability of the laser output by changing its pumping current. The change of the current is also introduced by a nonlinear map. The most important element of this nonlinear map is a dynamical variable parameter. We have studied the dynamic behavior of the laser before and after applying the control using bifurcation curves and time series. We have shown that the laser output, in the intervals of the feedback phase and strength where it is chaotic, can be totally inverted to the quasi periodic (QP) and period one (P1) oscillation modes, by control method. 相似文献
27.
Farhad Shirini Nader Ghaffari Khaligh Gholam Hossein Imanzadeh Parisa Ghods Ghasem-Abadi 《中国化学快报》2012,23(10):1145-1148
1,3-Dibromo-5,5-dimethylhydantoin,has been used as an efficient catalyst for the synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes in the presence of kaolin.All reactions are performed in the absence of solvent in relatively short reaction times in good to high yields. 相似文献
28.
Shirini Farhad Goli-Jolodar Omid Akbari Maryam Seddighi Mohadeseh 《Research on Chemical Intermediates》2016,42(5):4733-4749
Research on Chemical Intermediates - A novel Brønsted solid acid named poly(vinylpyrrolidonium) hydrogen phosphate ([PVP-H]H2PO4) has been prepared by using H3PO4 and poly(vinylpyrrolidone) as... 相似文献
29.
Mohammad Ali Zolfigol Farhad Shirini Khosrow Zamani Efat Ghofrani Satar Ebrahimi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2177-2182
Silica phosphoric acid was prepared via reaction of silica chloride (I) and phosphoric acid. Thiols can be readily converted to their corresponding thionitrites with a combination of silica phosphoric acid (II), wet SiO 2 , and sodium nitrite in dichloromethane at room temperature. Disulfides result from the homolytic cleavage of the sulfur–nitrogen bond of the unstable thionitrite and subsequent coupling of the resultant thiyl radicals. 相似文献
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