L∞ variational problems and weak KAM theory

In the first part of this paper, we extend several results in Crandall, Evans, and Gariepy [11] and Crandall and Evans [10] to absolute minimizers of more general L^∞ functionals. In the second part, we present some interesting connections between L^∞ variational problems and weak KAM theory. As an application, we will advance the main result in Fathi and Siconolfi [17], i.e, the existence of a C¹ subsolution of the Hamilton‐Jacobi equation. Moreover, we will propose a possible approximation of the projected Aubrey set by a variational approach that was first used by Evans in [14]. © 2007 Wiley Periodicals, Inc.     

The magnetic properties of Be-codoped GaMnN grown via molecular beam epitaxy

GaMnN and Be-codoped GaMnN were grown via molecular beam epitaxy using a single GaN precursor and their structural and magnetic properties were examined. X-ray diffraction and superconducting quantum interference device (SQUID) measurements revealed that the grown layers are homogeneous without precipitates. The saturation magnetization of GaMnN has increased from ∼4 to ∼16 emu/cm³ via codoping of Be. The d–d exchange interaction between Mn atoms was discussed for the ferromagnetism of GaMnN.     

Laser ablation lithography on thermoelectric semiconductor

In this paper, experimental results of the investigation of the periodic structure on thermoelectric semiconductor Cu₂Se are presented. Periodic structures were formed on surfaces of semiconductors due to multi-beam interaction of Q-switched Nd:YAG laser, which was operated in the lowest order of Gaussian mode and pulse duration 7 ns. Surface temperature evolution and transient reflectivity are studied during laser treatment. Creation of Cu islands in the maximal intensity of interference pattern was found.     

On the topological representation of catalytic cycles with nonlinear steps

Reaction route analysis is applied to visualize reaction networks in several heterogeneous catalytic reactions. Combination of the theory of complex reactions with the notion of catalytic cycles results in a topological representation of complex mechanisms with the nodes comprising all possible surface species including free sites and branches indicating interconnections between reactions.     

Achievements in the field of proton-conductive portion electrolyte membranes

The 2000–2006 achievements in the field of synthesis, property examination, and application of proton-exchange membranes are reviewed on the basis of more than 120 papers.     

Asymptotic speeds of spread and traveling waves for monotone semiflows with applications

The theory of asymptotic speeds of spread and monotone traveling waves is established for a class of monotone discrete and continuous‐time semiflows and is applied to a functional differential equation with diffusion, a time‐delayed lattice population model and a reaction‐diffusion equation in an infinite cylinder. © 2005 Wiley Periodicals, Inc.     

Pressure pulse from a laser pulse acting on a composite

Conclusions These tests on quasistationary irradiated for polyethylene-matrix powder-filled composites show that the filler composition and content have marked effects on the damage.There are ranges where the specific loss, the pressure, and the integral recoil pulse decrease as the power density increases because of changes in the damage mechanism, which are most prominent for zirconium oxide as filler. Bulk absorption contributes considerably, and causes various types of defect. Estimates have been made of the pressures arising in explosive matrix decomposition in the bulk together with the specific damage energies.These measurements are useful in modeling laser effects on composites.Translated from Mekhanika Kompositnykh Materialov, No. 5, pp. 868–872, September–October, 1988.     

Enantioseparation of Dencichine and D-Isomer on L-Cysteine Derivative Phase by Ligand-exchange Chromatography

Dencichine (β-N-oxalyl-L-α, β-diaminopropionic acid, L-ODAP), a nonprotein amino acid, is a haemostatic agent present in important Chinese medicinal herbs such as Panax notoginseng, as well as other Panax species1. It was first isolated from the seeds …     

Clathrate formation in the tetraisoamylammonium propionate-water system

In this paper we examine clathrate formation in the tetraisoamylammonium propionate-water binary system. We have found formation of four polyhydrates, two of which are metastable over the whole temperature range studied. All polyhydrate crystals were isolated and their compositions and densities determined; for (i-C₅H₁₁)₄NC₂H₅COO·36.5H₂O, unit cell parameters were additionally found. The results are compared with data for tetra-n-butylammonium carboxylate polyhydrates, and the structure of the title compounds is suggested. It is confirmed that the isoamyl radical stabilizes the tetradecahedral void of the clathrate hydrate framework better than the n-butyl radical. Institute of Inorganic Chemistry, Siberian Branch, Russian Academy of Sciences. Translated fromZhurnal Strukturnoi Khimii, Vol. 35, No. 3, pp. 67–71, May–June, 1994. Translated by L. Smolina     

Photochemistry of dibenzo-1,4-dioxins: intramolecular rearrangement-reduction through observable 2,2′-biphenylquinones

The photochemistry of dibenzo-1,4-dioxin (7) and 2,3,7,8-tetramethyldibenzo-1,4-dioxin (15) — both of which have the parent ring system of the well-known enrimental contaminant dioxin— has been studied in aqueous solution and in selected organic solvents. It is shown that a novel intramolecular photorearrangement is the major mode of reaction for 7 and the exclusive reaction for 15, giving rise to observable (by UV—Vis spectrophotometry) intermediate 2,2′-biphenylquinones. Subsequent reduction by the organic co-solvent gives rise to 2,2′-biphenols as major or exclusive product. Thus, photolysis of these compounds generates oxidizing agents in the biphenylquinones. Photolysis in the presence of added N_aBH₄ resulted is greatly enhanced yields of biphenols along with more than 90% material balance. These findings have relevance to dioxin photodecomposition, which can be used as a method for its destruction.