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131.
132.
Microwave induced d.c. voltage due to inverse a.c. Josephson effect has been observed across bulk samples of multiphase Y2BaSrCu3O8. Results indicate that weakly coupled superconducting grains probably exist up to 26°C. 相似文献
133.
134.
C. Jayaram 《Czechoslovak Mathematical Journal》2003,53(2):351-363
In this paper we investigate prime divisors, B
w-primes and zs-primes in C-lattices. Using them some new characterizations are given for compactly packed lattices. Next, we study Noetherian lattices and Laskerian lattices and characterize Laskerian lattices in terms of compactly packed lattices. 相似文献
135.
136.
DS Wragg MG O'Brien FL Bleken M Di Michiel U Olsbye H Fjellvåg 《Angewandte Chemie (International ed. in English)》2012,51(32):7956-7959
The movement of reactants in a large methanol-to-olefin reactor bed was visualized by fast scanning synchrotron X-ray diffraction. Changes in the structure of the catalyst showed the formation of reaction intermediates and coke, which can be tracked along the reactor bed. The observations lead to a new model for the progress of the reaction and explain the role of methanol in coke formation. 相似文献
137.
The design and development of novel squaraine dyes as sensitisers for photodynamic therapy (PDT) applications has grown tremendously in the last decade from the time when a squaraine dye was proposed to be a potential candidate, to-date when the use of such dyes have been demonstrated in animal models for skin cancer. This perspective article highlights the basic design, tuning of absorption, triplet excited state and two-photon absorption properties and recent developments of the squaraines as PDT sensitisers. 相似文献
138.
Pandya P Gupta SP Pandav K Barthwal R Jayaram B Kumar S 《Natural product communications》2012,7(3):305-309
Fluorescence studies on the indole alkaloids vinblastine sulfate, vincristine sulfate, vincamine and catharanthine have demonstrated the DNA binding ability of these molecules. The binding mode of these molecules in the minor groove of DNA is non-specific. A new parameter of the purine-pyrimidine base sequence specificty was observed in order to define the non-specific DNA binding of ligands. Catharanthine had shown 'same' pattern of 'Pu-Py' specificity while evaluating its DNA binding profile. The proton resonances of a DNA decamer duplex were assigned. The models of the drug:DNA complexes were analyzed for DNA binding features. The effect of temperature on the DNA binding was also evaluated. 相似文献
139.
Jayaram K. Sankaran 《Mathematical Programming》1993,61(1-3):171-195
This paper addresses the problem of minimizing the number of columns with superdiagonal nonzeroes (viz., spiked columns) in a square, nonsingular linear system of equations which is to be solved by Gaussian elimination. The exact focus is on a class of min-spike heuristics in which the rows and columns of the coefficient matrix are first permuted to block lower-triangular form. Subsequently, the number of spiked columns in each irreducible block and their heights above the diagonal are minimized heuristically.We show that ifevery column in an irreducible block has exactly two nonzeroes, i.e., is a doubleton, then there is exactly one spiked column. Further, if there is at least one non-doubleton column, there isalways an optimal permutation of rows and columns under whichnone of the doubleton columns are spiked.An analysis of a few benchmark linear programs suggests that singleton and doubleton columns can abound in practice. Hence, it appears that the results of this paper can be practically useful. In the rest of the paper, we develop a polynomial-time min-spike heuristic based on the above results and on a graph-theoretic interpretation of doubleton columns. 相似文献
140.
C. Jayaram 《Czechoslovak Mathematical Journal》2002,52(3):585-593
In this paper we study primary elements in Prüfer lattices and characterize -lattices in terms of Prüfer lattices. Next we study weak ZPI-lattices and characterize almost principal element lattices and principal element lattices in terms of ZPI-lattices. 相似文献