Symplectic Topology of Integrable Hamiltonian Systems, II: Topological Classification

The main purpose of this paper is to give a topological and symplectic classification of completely integrable Hamiltonian systems in terms of characteristic classes and other local and global invariants.     

On the eddy diffusivities for momentum and heat

Summary From a simple consideration, the eddy diffusivities for momentum and heat are shown to be equal in terms of statistical properties of turbulence. A universal semi-empirical expression for the eddy diffusivities in a turbulent shear flow is obtained in terms of the distance from the solid boundary and flow properties.     

Anisotropic wet etching on birefringent calcite crystal

In this paper, a mechanism for wet etching on birefringent calcite crystal is discussed. By altering the etchant type, its concentration and the stirring speed, the etching mechanism can be confined within the surface reaction regime, resulting in anisotropic etching. Acetic acid can be used to form V shapes defined by the {101̄1} planes with an intersecting angle of 51 degree. V-groove and blazed grating, with a grating period as small as 2 μm, were successfully fabricated. Such gratings can be used as transmission and reflection devices in the visible and infrared ranges. In addition, a transmission polarization dependent device can also be made by covering the calcite with index matching material. PACS 42.70.-a; 42.79.Dj     

Tetrahydrofuran Activation Assisted Synthesis of Nanosized Lithium Niobate and Lithium Tantalate

Black solid precursors obtained from reactions between MCl₅ (M = Nb, Ta) and alkyllithiums, n‐butyllithium (ⁿBuLi) and ethyllithium (EtLi), in tetrahydrofuran (THF) were heat treated under vacuum at 673–973 K to form nano‐sized particles (20–100 nm in diameter) of lithium niobate (LiNbO₃) and lithium tantalate (LiTaO₃). Stoichiometry of the reactants is critical and affects the phases of the products. Based on the volatile byproducts detected, a reaction pathway involving the activation of THF by alkyllithiums is proposed to be important for the formation of LiNbO₃ and LiTaO₃ precursors.     

Sydnones IV. Synthesis of Sydnones Analogous to the Photochromic Compounds

N-(6-methoxy-3-pyridyl)-sydnone (I), N-(4-nitrobenzyl)sydnone (II-1), and N-(2-nitrobenzyl)sydnone (II-2) have been prepared. Condensation of 2, 4-dinitrochlorohenzene with N-(carbethoxymethyl)sydnone (II-4) produced N-[(2, 4-dinitrophenyl) carbethoxymethyl]-sydnone (II-5). Under normal conditions none of them are photochromic.     

Bilayer lipid membranes formed from thermotropic liquid crystals

This paper reports a new type of bilayer lipid membrane (BLM) with aqueous interfaces which are formed from thermotropic liquid crystals (nematic-6CB, smectic-8CB, and cholesteric-cholesteryl palmitate, ChP). The electrical properties of these unmodified membranes have been investigated. We suggest that BLMs of this type in their 'black' states consist of two molecular layers with a smectic-like structure.