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81.
Path integration of a class of generalized quadratic actions first proposed by Feynman is performed within the framework of Feynman's polygonal path approach. The exact propagator has the form of a free particle propagator with an “effective mass” apart from the normalization factor. Relation between the propagator and the usual Van Vleck-Pauli formula is discussed. 相似文献
82.
In this paper we propose a perfect teleportation protocol for certain class of three-qubit entangled states. The class of states which are teleported, is larger than those considered by Nie et al. (Int. J. Theor. Phys. 50, 2799 46) and Li et al. (Int. J. Theor. Phys. 47). We use cluster states as quantum channels. The paper is in the line of research for quantum mechanically transporting multiparticle entangled states. 相似文献
83.
Surajit Ghosh 《Tetrahedron》2008,64(7):1250-1256
The triskelion peptide conjugate 1, having a Trp-Trp dipeptide unit on the three arms, was synthesized and studied for the interaction of peptide-based soft structures with metal ions, by fluorescence and microscopic analyses. We observed that fluorescence was significantly quenched upon addition of Cu(II) metal ions, whereas the addition of other metal ions also caused moderate to insignificant changes in the fluorescence emission, suggesting specificity of this triskelion peptide 1 for Cu(II) ions. The addition of Cu(II) and other metal ions also altered the morphology of preformed vesicles obtained from triskelion peptide 1 in a concentration-dependent fashion, as observed from microscopic analysis. Such metal-responsive soft structures may find potential use as novel materials for delivery and sensing applications. 相似文献
84.
Sinan M Panda M Ghosh A Dhara K Fanwick PE Chattopadhyay DJ Goswami S 《Journal of the American Chemical Society》2008,130(15):5185-5193
An efficient synthesis of a family of heteroaromatic triazinium compounds, [2a]X-[2g]X (X = Cl, ClO4, NO3, and HSO4), from 2-(arylazo)pyridines via proton-catalyzed heterocyclization is described. Characterization of the compounds is made by different spectroscopic, electrochemical techniques, as well as single-crystal structure determination of the triflate salt of a representative compound, [2a]CF3SO3. The bond parameters indicate that the tricyclo compound, 2a(+), is planar and aromatic with a N-N bond length of 1.275(6) A. These exhibited fluorescence with an emission maximum in the range of 540-535 nm with moderate quantum yields. The triazinium salts can be reduced in two successive one-electron steps as probed by cyclic voltammetry and coulometry. The paramagnetic radical intermediate 2a(*) is distinguished by a sharp and intense EPR spectrum. Fluorescence spectroscopy, circular dichroism, cyclic voltammetry, viscosity measurements, together with DNA melting studies have been used to characterize the binding of 2a(+) with calf thymus DNA. The emission quenching of the compound by [Fe(CN)6](4-) decreased when bound to DNA. As determined by a MTT assay, 2a(+) exhibited significant cytotoxicity at a higher concentration range of 1 mg/mL to 1 microg/mL; however, the % survival ratio increased with dilution. Cellular uptake studies of the referenced compound were followed by FACS analysis. 相似文献
85.
86.
The microscopic basis of Newton's law of cooling and its modification when the difference in temperature between the system and the surroundings is very large is discussed. When the system of interest is interacting with a small bath, the effect of the dynamical evolution of the bath variables is important to find out its dynamical feedback on the system. As in the usual system-bath approach, however, the bath is finally considered to be in thermal equilibrium and thereby provides an effective generalization of the Born-Markov master equation. It is shown that the cooling at early time is faster than that predicted by Newton's law due to the dynamical feedback of the bath. 相似文献
87.
Prakash Amrita Dhara Mishra R. K. Valsala T. P. Sharma V. Acharya R. Tyagi A. K. Pujari P. K. Kaushik C. P. 《Journal of Radioanalytical and Nuclear Chemistry》2021,328(2):519-526
Journal of Radioanalytical and Nuclear Chemistry - An attempt was made to increase the solubility of High Level liquid Waste (HLW), mainly Cr and Mo, by addition of P2O5 to sodium borosilicate... 相似文献
88.
A stereoselective total synthesis of 10-epi-tirandamycin E is described, employing desymmetrization protocol, ring-closing metathesis (RCM), acid-catalyzed ketalization, substrate controlled dihydroxylation and Horner-Wadsworth-Emmons olefination as key reactions. 相似文献
89.
90.
Dr. Surajit Some Sun Jun Kim Prof. Seong Chan Jun 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(44):15480-15485
A simple and easy process has been developed to efficiently dope phosphorus into a graphene oxide surface. Phosphorus‐doped graphene oxide (PGO) is prepared by the treatment of polyphosphoric acid with phosphoric acid followed by addition of a graphene oxide solution while maintaining a pH of around 5 by addition of NaOH solution. The resulting materials are characterized by X‐ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FT‐IR), X‐ray diffraction (XRD), Raman spectroscopy, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). The as‐made PGO solution‐coated cloth exhibits excellent flame retardation properties. The PGO‐coated cloth emits some smoke at the beginning without catching fire for more than 120 s and maintains its initial shape with little shrinkage. In contrast, the pristine cloth catches fire within 5 s and is completely burned within 25 s, leaving trace amounts of black residue. The simple technique of direct introduction of phosphorus into the graphene oxide surface to produce phosphorus‐doped oxidized carbon nanoplatelets may be a general approach towards the low‐cost mass production of PGO for many practical applications, including flame retardation. 相似文献