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131.
Lucia Buenrostro Amrita Dhillon Myrna Wooders 《International Journal of Game Theory》2007,35(3):353-377
Protests take place for a variety of reasons. In this paper we focus on protests that have a well defined objective that is
in conflict with the objectives of the government. Hence the success or failure of a protest movement depends crucially on
how the government responds. We assume that government types are private information so that governments have an interest
in building a reputation to deter protestors. We extend the standard reputation framework to one where potential protesters
in the domestic jurisdiction are competing in a common market with protestors of a foreign jurisdiction, resulting in a situation
where domestic governments care about the decisions of foreign governments. We derive conditions under which an equilibrium
with “contagion” in protests might exist: protests that start in one jurisdiction spread to others. Finally we use our results
to interpret the Fuel tax protests in France and England that took place in 2000 as well as the three successive pro-democracy
revolutions in Georgia, Ukraine and Kyrgyzstan. 相似文献
132.
Amrita Mukherjee S.S. Bhattacharyya B.K. Chaudhuri S.L. Wu 《Journal of Molecular Liquids》2009,148(2-3):127-131
Polymethylmethacrylate (PMMA) and ferroelectric liquid crystal (P–FLC) composite films (~ 4 μm) with varying proportions of ferroelectric liquid crystal have been prepared and the dielectric response of the composite films as a function of wide frequency (100 Hz–10 MHz) and temperature (127–40 °C) have been analyzed. The dielectric spectra of such composite systems are considerably modified compared to those of the corresponding pure LC or PMMA materials. The observed paraelectric to ferroelectric transition temperature of the composites is found to be lower (~ 85 °C) compared to that of the pure LC system (~ 98 °C), which makes these composites technologically more significant. The P–FLC composites also exhibit higher relaxation frequency and smaller dielectric strength for the Goldstone mode compared to those of the corresponding pure FLC. Depending on the percentage of the constitute materials, the molecular dynamics of the composite materials changes. Dielectric contributions of both liquid crystal and PMMA matrix forming the composites have been analyzed on the basis of Havriliak and Negami function. 相似文献
133.
[reaction: see text] The formation of nitrone (a water exclusion reaction) in aqueous media using surfactant and subsequent cycloaddition in the same pot, a new example of green chemistry, is reported. The control of regioselectivity favors the formation of trans-5-substituted isoxazolidine. This work not only may lead to an environmentally benign system but also will provide a new aspect of reactions in water. 相似文献
134.
Sharmistha Paul Eva Bladt Alexander F. Richter Markus Dblinger Yu Tong He Huang Amrita Dey Sara Bals Tushar Debnath Lakshminarayana Polavarapu Jochen Feldmann 《Angewandte Chemie (International ed. in English)》2020,59(17):6794-6799
The concept of doping Mn2+ ions into II–VI semiconductor nanocrystals (NCs) was recently extended to perovskite NCs. To date, most studies on Mn2+ doped NCs focus on enhancing the emission related to the Mn2+ dopant via an energy transfer mechanism. Herein, we found that the doping of Mn2+ ions into CsPbCl3 NCs not only results in a Mn2+‐related orange emission, but also strongly influences the excitonic properties of the host NCs. We observe for the first time that Mn2+ doping leads to the formation of Ruddlesden–Popper (R.P.) defects and thus induces quantum confinement within the host NCs. We find that a slight doping with Mn2+ ions improves the size distribution of the NCs, which results in a prominent excitonic peak. However, with increasing the Mn2+ concentration, the number of R.P. planes increases leading to smaller single‐crystal domains. The thus enhanced confinement and crystal inhomogeneity cause a gradual blue shift and broadening of the excitonic transition, respectively. 相似文献
135.
Dharmendra Das Zigmee T. Bhutia Padmini C. Panjikar Amrita Chatterjee Mainak Banerjee 《Journal of heterocyclic chemistry》2020,57(11):4099-4107
A green and efficient mechanochemical method for the synthesis of a series of 2-arylimidazo[1,2-a]pyridines was developed using an electrical grinder. I2 catalyzed mechanochemical grinding facilitates the cyclocondensation reaction between various aryl methyl ketones and 2-aminopyridines to afford 2-arylimidazo[1,2-a]pyridines in good yields at ambient temperature. The method was successfully used for the gram-scale synthesis of a marketed drug, zolimidine. The noticeable advantages of this environmentally sustainable protocol include mild conditions, simple instrumentation, inexpensive catalyst, atom economy, short reaction time etc. 相似文献
136.
Full DFT based quantum mechanical studies reveal that zero dimensional porous structures, especially the newly proposed phosphorus incorporated organic cages, can be excellent catalysts for the dehydrogenation of ammonia borane. 相似文献
137.
Pritha Ghosh G. Poornima Devi R. Priya A. Amrita A. Sivaramakrishna S. Babu R. Siva 《Applied biochemistry and biotechnology》2013,170(5):1127-1137
Anthraquinones consist of several hundreds of derivatives that differ in the nature and positions of substituent groups which are known to have several biological activities including antitumor properties. Interaction of molecules with DNA persists to be an extremely vital parameter while endeavouring to formulate therapeutics. In this study, few anthraquinone derivatives such as 1,2-dihydroxyanthraquinone (alizarin), 1,4-dihydroxyanthraquinone (quinizarin), 1,8-dihydroxyanthraquinone (danthron), 1,2,4-trihydroxyanthraquinone (purpurin), 1,4-diaminoanthraquinone, and 1-methylaminoanthraquinone were analyzed for its possible interaction with calf-thymus DNA through spectroscopy and in silico analysis. Our UV spectroscopic results indicate that all selected anthraquinones interact with DNA probably by external binding. Molar extinction coefficient has been calculated for chosen six anthraquinones. FT-IR results suggest that significant shifts of peaks as well as disappearance of certain characteristic peaks were indicators of the plausible interaction going on due to dye-DNA adduct formation. Among the six dyes used, purpurin showed better results and indicates the relatively strong binding affinity with DNA. Our molecular modeling results also show that purpurin has comparatively higher DNA interaction with a score of ?6.18 compared with the ethidium bromide of ?5.02 and intercalate the DNA. 相似文献
138.
Amrita Pal 《Supramolecular chemistry》2013,25(1-2):127-135
A series of N-(n-alkylcarbamoyl)-l-amino acid amphiphiles with different amino acid head groups were designed and synthesised. The gelation abilities of these amphiphilic molecules were studied in toluene and p-xylene solvents. The hypothesis that steric crowding at the chiral head group destroys gelation ability of the amphiphile was examined. Indeed, beside l-alanine-based amphiphile, only l-serine and l-aspartic acid derivatives were found to gelate the organic liquids efficiently in the presence of a small quantity of water. The gels were characterised by a number of methods, including FT-IR, NMR and X-ray diffraction spectroscopy, scanning electron microscopy (SEM) and rheology. The SEM micrographs revealed three-dimensional networks of ribbon-like aggregates. The organogels were observed to be thermo-reversible in nature and have sufficient mechanical strength. The gels have gel-to-sol transition temperatures above the physiological temperature (310 K). 相似文献
139.
Amrita ChakrabortySurajit Sinha 《Tetrahedron letters》2011,52(49):6635-6638
A three-step procedure has been developed for the synthesis of 3-[2-(1,3-butadienyl)]-1H-indoles. TBAF was proved to be an effective reagent for dehydrobromination and carbomethoxy deprotection in one step to give 3-[2-(1,3-butadienyl)]-1H-indoles from the corresponding bromo-derivatives. Suitably substituted indolyl-1,3-butadiene has been successfully applied to prepare murrapanine analogue via Diels-Alder reaction. 相似文献
140.
Jessica Berrones Reyes Peter S. Sherin Amrita Sarkar Marina K. Kuimova Ramon Vilar 《Angewandte Chemie (International ed. in English)》2023,62(42):e202310402
G-quadruplex DNA is a non-canonical structure that forms in guanine-rich regions of the genome. There is increasing evidence showing that G-quadruplexes have important biological functions, and therefore molecular tools to visualise these structures are important. Herein we report on a series of new cyclometallated platinum(II) complexes which, upon binding to G-quadruplex DNA, display an increase in their phosphorescence, acting as switch-on probes. More importantly, upon binding to G-quadruplexes they display a selective and distinct lengthening of their emission lifetime. We show that this effect can be used to selectively visualise these structures in cells using Phosphorescence Lifetime Imaging Microscopy (PLIM). 相似文献