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Crystallography Reports - The communication deals with the eco-friendly synthesis and X-ray crystal structure of an organic carbonitrile, namely... 相似文献
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Goutam Dutta Krishnendranath Mitra 《The Journal of the Operational Research Society》2017,68(10):1131-1145
Revenue management and dynamic pricing are concepts that have immense possibilities for application in the energy sector. Both can be considered as demand-side management tools that can facilitate the offering of different prices at different demand levels. This paper studies literature on various topics related to the dynamic pricing of electricity and lists future research avenues in pricing policies, consumers’ willingness to pay and market segmentation in this field. Demand and price forecasting play an important role in determining prices and scheduling load in dynamic pricing environments. This allows different forms of dynamic pricing policies to different markets and customers depending on customers’ willingness to pay. Consumers’ willingness to pay for electricity services is also necessary in setting price limits depending on the demand and demand response curve. Market segmentation can enhance the effects of such pricing schemes. Appropriate scheduling of electrical load enhances the consumer response to dynamic tariffs. 相似文献
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Dr. Nayana Nayek Prof. Dr. Goutam Brahmachari 《European journal of organic chemistry》2023,26(2):e202201343
A photochemical method based on visible-light (white LEDs/sunlight) irradiation has been developed for the regioselective and oxidative C(sp2)−H selenylation and sulfenylation of substituted 2-amino-1,4-naphthoquinones under oxygen atmosphere. The photochemical process does not require any external photoredox catalysts. The other notable advantages of this protocol are metal-free synthesis, visible light/sunlight as energy sources, good substrate scope, and moderate to good yields (41–91 %) with high regioselectivity. 相似文献
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Dr. Goutam Kumar Kole Dr. Julia Merz Dr. Anissa Amar Dr. Bruno Fontaine Dr. Abdou Boucekkine Dr. Jörn Nitsch Sabine Lorenzen Dr. Alexandra Friedrich Dr. Ivo Krummenacher Marta Košćak Prof. Dr. Holger Braunschweig Prof. Dr. Ivo Piantanida Prof. Dr. Jean-François Halet Prof. Dr. Klaus Müller-Buschbaum Prof. Dr. Todd B. Marder 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(8):2837-2853
Two N-methylpyridinium compounds and analogous N-protonated salts of 2- and 2,7-substituted 4-pyridyl-pyrene compounds were synthesised and their crystal structures, photophysical properties both in solution and in the solid state, electrochemical and spectroelectrochemical properties were studied. Upon methylation or protonation, the emission maxima are significantly bathochromically shifted compared to the neutral compounds, although the absorption maxima remain almost unchanged. As a result, the cationic compounds show very large apparent Stokes shifts of up to 7200 cm−1. The N-methylpyridinium compounds have a single reduction at ca. −1.5 V vs. Fc/Fc+ in MeCN. While the reduction process was reversible for the 2,7-disubstituted compound, it was irreversible for the mono-substituted one. Experimental findings are complemented by DFT and TD-DFT calculations. Furthermore, the N-methylpyridinium compounds show strong interactions with calf thymus (ct)-DNA, presumably by intercalation, which paves the way for further applications of these multi-functional compounds as potential DNA-bioactive agents. 相似文献
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Sodium Formate‐Catalyzed One‐Pot Synthesis of Benzopyranopyrimidines and 4‐Thio‐substituted 4H‐Chromenes via Multicomponent Reaction at Room Temperature 下载免费PDF全文
A simple, straightforward and highly efficient multicomponent one‐pot synthesis of a series of pharmaceutically interesting benzopyranopyrimidine and 4H‐chromene derivatives has been developed on the basis of low‐cost and environment‐friendly sodium formate catalyst via tandem reactions of salicylic aldehydes, malononitrile, and cyclic secondary amines in ethanol at room temperature. Nature of nucleophile used in this reaction directs the course of the reaction; cyclic secondary amines result in the formation of benzopyrano[2,3‐d]pyrimidines, whereas thiophenol furnish corresponding 4‐thio‐subtituted 4H‐chromenes under the same reaction conditions. High atom‐economy, good yields, eco‐friendly, and mild reaction conditions are some of the important features of this protocol. 相似文献
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Subhamoy Maitra Goutam Paul Shashwat Raizada Subhabrata Sen Rudradev Sengupta 《Designs, Codes and Cryptography》2011,59(1-3):231-245
In this paper, we study HC-128 in detail from cryptanalytic point of view. First, we use linear approximation of the addition modulo 2 n of three n-bit integers to identify linear approximations of g 1, g 2, the feedback functions of HC-128. This, in turn, shows that the process of keystream output generation of HC-128 can be well approximated by linear functions. In this direction, we show that the ??least significant bit?? based distinguisher (presented by the designer himself) of HC-128 works for the complete 32-bit word. Using the above linear approximations of g 1, g 2, we present a new distinguisher for HC-128 which is slightly weaker than Wu??s distinguisher. Finally, in the line of Dunkelman??s observation, we also study how HC-128 keystream words leak secret state information of the cipher due to the properties of the functions h 1, h 2 and present improved results. 相似文献
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Sudip Kumar Bera Sudipta Mondal Arijit Singha Hazari Jos Luis Priego Reyes Jimnez‐Aparicio Wolfgang Kaim Goutam Kumar Lahiri 《化学:亚洲杂志》2020,15(16):2532-2543
The dianion derived from (2Z,6Z)‐3,7‐diphenyl‐N2,N6‐di(pyridin‐2‐yl)pyrrolo[2,3‐f]indole‐2,6(1H,5H)‐diimine (H2BL), a modified BODIPY ligand precursor, is shown to be capable of bridging two metal complex fragments RuL2, L=2,4‐pentanedionato (acac?), 2,2’‐bipyridine (bpy) or 2‐phenylazopyridine (pap) in [Ru(acac)2Ru(μ‐BL)Ru(acac)2] ( 1 / 2 ), [Ru(bpy)2Ru(μ‐BL)Ru(bpy)2](ClO4)2 ([ 3 ](ClO4)2) and [Ru(pap)2Ru(μ‐BL)Ru(pap)2](ClO4)2 ([ 4 ](ClO4)2). The compounds, including a diastereoisomeric pair 1 (meso) and 2 (rac) were spectroscopically and structurally characterized. Reversible electron transfers as revealed by cyclic and differential pulse voltammetry allowed for an EPR and UV‐vis‐NIR spectroelectrochemical investigation of several neighboring charge states. Together with susceptibility measurements and TD‐DFT calculations the assignment of oxidation states reveals that 1 , 2 are diruthenium(III) species which can be oxidized or reduced by one electron whereas 3 2+ and 4 2+ contain ruthenium(II) and get reduced or oxidized mainly at the dianionic bridge ( 3 2+) or are reduced at the ancillary ligands pap ( 4 2+). 相似文献
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