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991.
Amar Chandra Patra Mahendra Nath Sinha Roy Dipankar Ray 《International Journal of Theoretical Physics》1989,28(4):415-421
Padmanabhan derived a differential equation for the stationary state for the class A Bianchi model and obtained some approximate solutions. Here we reduce the differential equation to a standard, well-known, solvable linear differential equation and indicate some exact explicit particular solutions. 相似文献
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In an attempt to utilize the synthetic power of the furan nucleus in the synthesis of complex natural products, we have developed an entry into annulated furan intermediates that involves an electrochemical annulation protocol. An approach to the eunicellin diterpenes based on this methodology required the use of an intermolecular Diels-Alder reaction on an annulated furan. Although well known for simple furans, there is a paucity of related examples on annulated furans. To examine the feasibility of such an approach to these diterpenes, we have studied this key cycloaddition reaction. Our studies indicate that the process can be hampered by a facile retro-Diels-Alder that is highly dependent on the dienophile employed. 相似文献
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Following a sequential two-photon excitation, fluorescence is observed from several selectively excited single rotational-vibrational
energy levels of theE
3
π0
g
+
state of molecular iodine. The re-emittedE →B fluorescence spectrum from each of the populated rovibrational level of theE state consists of a series of sharp lines terminating on the various discrete ro-vibrational levels of theB state and a few broad lines due to transitions taking place on to the continuum of theB state. The point of transition from sharp lines to broad features in the fluorescence spectrum has been utilized to determine
theB state dissociation limit. This method of obtaining the dissociation limit of the molecular electronic states appears to be
quite simple and straightforward. 相似文献
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1000.
Milan V. Patel Jatin N. Patel Arabinda Ray Rajni M. Patel 《Journal of polymer science. Part A, Polymer chemistry》2005,43(1):157-167
4‐Chloro‐3‐methyl phenyl methacrylate (CMPM) and 8‐quinolinyl methacrylate (8‐QMA) were synthesized through the reaction of 4‐chloro‐3‐methyl phenol and 8‐hydroxy quinoline, respectively, with methacryloyl chloride. The homopolymers and copolymers were prepared by free‐radical polymerization with azobisisobutyronitrile as the initiator at 70 °C. Copolymers of CMPM and 8‐QMA of different compositions were prepared. The monomers were characterized with IR spectroscopy and 1H NMR techniques. The copolymers were characterized with IR spectroscopy. UV spectroscopy was used to obtain the compositions of the copolymers. The monomer reactivity ratios were calculated with the Fineman–Ross method. The molecular weights and polydispersity values of the copolymers were determined with gel permeation chromatography. The thermal stability of the polymers was evaluated with thermogravimetric analysis under a nitrogen atmosphere. The homopolymers and copolymers were tested for their antimicrobial activity againstbacteria, fungi, and yeast. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 157–167, 2005 相似文献