Interference effect in electron emission in heavy ion collisions with h2 detected by comparison with the measured electron spectrum from atomic hydrogen

Direct evidence of the interference effect in the electron emission spectra from ionization of molecular hydrogen in collisions with bare C and F ions at relatively low collision energies is presented. Oscillations due to the interference are deduced by comparing the measured double differential cross sections of the electrons emitted from molecular hydrogen to those emitted from atomic hydrogen, rather than using the calculated cross sections for H as in a previous report. We believe these experimental data provide stronger support for the evidence of the interference effect. We show that it is not only a feature of very high energy collisions, but also a feature to be observed in relatively lower energy collisions.     

Parallel bundle-based decomposition for large-scale structured mathematical programming problems

In this paper, we present parallel bundle-based decomposition algorithms to solve a class of structured large-scale convex optimization problems. An example in this class of problems is the block-angular linear programming problem. By dualizing, we transform the original problem to an unconstrained nonsmooth concave optimization problem which is in turn solved by using a modified bundle method. Further, this dual problem consists of a collection of smaller independent subproblems which give rise to the parallel algorithms. We discuss the implementation on the CRYSTAL multi-computer. Finally, we present computational experience with block-angular linear programming problems and observe that more than 70% efficiency can be obtained using up to eleven processors for one group of test problems, and more than 60% efficiency can be obtained for relatively smaller problems using up to five processors for another group of problems.     

Bundle-based decomposition for large-scale convex optimization: Error estimate and application to block-angular linear programs

Robinson has proposed the bundle-based decomposition algorithm to solve a class of structured large-scale convex optimization problems. In this method, the original problem is transformed (by dualization) to an unconstrained nonsmooth concave optimization problem which is in turn solved by using a modified bundle method. In this paper, we give a posteriori error estimates on the approximate primal optimal solution and on the duality gap. We describe implementation and present computational experience with a special case of this class of problems, namely, block-angular linear programming problems. We observe that the method is efficient in obtaining the approximate optimal solution and compares favorably with MINOS and an advanced implementation of the Dantzig—Wolfe decomposition method.     

Redox isomerization via azomethine ylide intermediates: N-alkyl indoles from indolines and aldehydes

Indolines react with aromatic and heteroaromatic aldehydes to yield N-alkyl indoles in a benzoic acid catalyzed redox isomerization reaction. Azomethine ylides are intermediates in this process which was established by intramolecular [3 + 2] trapping experiments.     

The decarboxylative Strecker reaction

α-Amino acids react with aldehydes in the presence of a cyanide source to form α-amino nitriles in what can be considered a decarboxylative variant of the classical Strecker reaction. This unprecedented transformation does not require the use of a metal catalyst and provides facile access to valuable α-amino nitriles that are inaccessible by traditional Strecker chemistry.     

A Least-Squares Mixed Scheme for the Simulation of Two-Phase Flow in Porous Media on Unstructured Grids

A least-squares mixed formulation is developed for simulation of two-phase flow in porous media. Such problems arise in petroleum applications and ground-water flow. An adaptive strategy based on the element residual as an error indicator is developed in conjunction with unstructured remeshing and tested for the two-phase flow of oil and water. An element-by-element conjugate-gradient scheme (EBE-CG) is compared to a band solution algorithm.     

Purification,Characterisation and Cloning of a 2S Albumin with DNase,RNase and Antifungal Activities from Putranjiva Roxburghii

The present study reports the characterisation of a novel ~12-kDa heterodimeric protein, designated as putrin, from the seeds of Putranjiva roxburghii. The purification of putrin to homogeneity was accomplished using DEAE-sepharose where protein was unbound, CM-sepharose and Cibacron blue 3GA where it was bound and appeared as single peak on a size-exclusion chromatography column. A 15 % sodium dodecyl sulphate polyacrylamide electrophoresis gel, under reducing condition, demonstrated that putrin is made of two polypeptide chains of approximately 4.5 and 7.5 kDa. Circular dichroism studies demonstrated the helical nature and conformational stability of protein at increasing temperatures. Putrin exhibited both RNase and DNase activities and exerted antifungal activity but possessed relatively weak translation–inhibitory activity in cell-free system. The cloning and sequence analysis revealed a 414 bp open reading frame encoding a preproprotein of 137 amino acid residues. The amino acid sequence comparisons and phylogenetic analysis of putrin showed significant homology to 2S seed storage family proteins. The results demonstrated that putrin belongs to 2S albumin family and exhibits a spectrum of biotechnologically exploitable functions.