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11.
Optics has already showed its potency over its electronic complements in case of superfast computing and communication systems. Semiconductor optical amplifier, (SOA) with its several nonlinear properties, plays a very crucial role in the development of high-speed all-optical processor. Multiplexer and demultiplexer are the extremely important element of the processor which takes part in utilizing different actions like encoding, decoding, routing, and the different process of data conversion and generation, etc. In this paper, the authors have proposed a scheme of phase encoded all-optical phase multiplexer using four wave mixing (FWM) property of semiconductor optical amplifier. Thus, the improved tolerance against fiber-nonlinearity and higher receiver sensitivity of phase encoding method with the fast occurring processes like FWM in SOA offers higher speed in this proposed scheme of multiplexing. 相似文献
12.
Subhendu Mondal 《Supramolecular chemistry》2013,25(10):645-652
ABSTRACTPerimedine labelled rhodamine dye 1 has been designed and synthesised. Metal ion binding studies of 1 have been performed in CH3CN/H2O (3:1, v/v, 10 mM Tris-HCl buffer, pH = 6.90). Compound 1 senses multiple metal ions such as Al3+, Fe3+ and Fe2+ by exhibiting turn on fluorescence and colour change (colourless to pink) under different experimental conditions. Concentration variation distinguishes Al3+ from Fe3+ ion. At low concentration (c = 1 x 10?4 M), only Al3+ ion can exhibit turn on fluorescence with sharp colour change. Sensing of Fe2+ ion through turn on fluorescence and colour change has been possible via in situ oxidation by following Fenton’s reaction. 相似文献
13.
Seetaram Mohapatra Chittaranjan Bhanja Satyaban Jena Subhendu Chakroborty Sabita Nayak 《合成通讯》2013,43(15):1993-2007
The Bestmann–Ohira reagent serves as a versatile platform for the regioselective construction of pyrazoles, triazoles, and oxazoles via a cycloaddition reaction and multicomponent reaction. In this review, we have summarized the most significant advances in the Bestmann–Ohira reagent (BOR)–assisted construction of functionalized five–membered heterocycles reported in the literature up to 2012. 相似文献
14.
Shuvankar Naskar Rweetuparna Guha Jens Müller 《Angewandte Chemie (International ed. in English)》2020,59(4):1397-1406
The incorporation of metal ions into nucleic acids by means of metal‐mediated base pairs represents a promising and prominent strategy for the site‐specific decoration of these self‐assembling supramolecules with metal‐based functionality. Over the past 20 years, numerous nucleoside surrogates have been introduced in this respect, broadening the metal scope by providing perfectly tailored metal‐binding sites. More recently, artificial nucleosides derived from natural purine or pyrimidine bases have moved into the focus of AgI‐mediated base pairing, due to their expected compatibility with regular Watson–Crick base pairs. This minireview summarizes these advances in metal‐mediated base pairing but also includes further recent progress in the field. Moreover, it addresses other aspects of metal‐modified nucleic acids, highlighting an expansion of the concept to metal‐mediated base triples (in triple helices and three‐way junctions) and metal‐mediated base tetrads (in quadruplexes). For all types of metal‐modified nucleic acids, proposed or accomplished applications are briefly mentioned, too. 相似文献
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Subhendu K. Datta 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1964,15(2):175-183
Zusammenfassung Es wird für das Problem der Wärmespannungen in einem kegelförmig begrenzten elastischen Körper eine Ähnlichkeitstransformation entwickelt. Ist die Temperatur an der freien Oberfläche als Potenz des Abstandes von der Spitze vorgeschrieben, so lässt sich ein Satz von Ähnlichkeitsvariablen angeben, welcher die thermoelastischen Beziehungen auf Legendre-Gleichungen reduziert und damit der Lösung leicht zugänglich macht. Die Rechnung ist für den Sonderfall konstant gehaltener Oberflächentemperatur im einzelnen durchgeführt.
This work has been done at the Mathematics Research Center, University of Wisconsin, under the U.S. Army Contract DA-11-022-ORD-2059. 相似文献
This work has been done at the Mathematics Research Center, University of Wisconsin, under the U.S. Army Contract DA-11-022-ORD-2059. 相似文献
18.
The adsorption profiles of free and Daunomycin bound DNA at an alumina–H2O interface have been studied. Proper experimental conditions were maintained to considerably reduce intercalation and to make electrostatic binding predominant in the DNA–Daunomycin complex. For both free and complexed DNA, Langmuir plots gave straight lines. Adsorption of drug bound DNA was less than that of free DNA. This has been explained from the viewpoint of electrostatic interactions between adsorbate and adsorbent. A Langmuir-type model for adsorption of polymers combined with Scatchard equation have been used to estimate the average value of percent of phosphates in DNA stacked with Daunomycin. 相似文献
19.
Novel enediynyl amino acids and peptides 3 and 5-8 were synthesized and their thermal reactivity towards Bergman cyclization studied and compared with the earlier reported amino acid 4, which demonstrated, for the first time, the effect of H-bonding and electrostatic interactions in lowering the activation energy of Bergman cyclization. 相似文献
20.
Rupankar PairaArindam Maity Shyamal MondalSubhendu Naskar Krishnendu B. SahuPritam Saha Abhijit HazraE. Padmanaban Sukdeb BanerjeeNirup B. Mondal 《Tetrahedron letters》2011,52(14):1653-1657
Basic alumina supported solvent-free one-pot synthesis of pyridine-fused polycyclic diazepaniums was achieved under microwave irradiation. The process was successfully extended to the synthesis of pyridine-fused bicyclic imidazolidiniums and tetrahydro-pyrimidiniums and also of tri- and tetracyclic diaza-heterocycle-fused quinoliniums. The dual characteristic of basic alumina, a solid support as well as a base, was successfully employed in the current investigation. The method emerged to be an effective route in terms of product yield, reaction time, and ease of purification and most importantly for environment friendly protocols. 相似文献