A liquid derivative of 12-tungstophosphoric acid with unusually high conductivity

Surface functionalization of the solid heteropolyacid H3PW12O40 with a bulky PEG-containing quaternary ammonium cation through partial proton exchange leads to a polyoxometalate-based liquid salt with high-temperature proton conductivity ( approximately 10-3 S cm-1 at 140 degrees C) under dry conditions. The proton conductivity of the liquid salt is 4 orders of magnitude higher than that of the solid analogue under identical conditions and shows super ionic behavior as defined by Walden plot.     

Front initiation on microdesigned composite catalysts

We first briefly review the subject of spatiotemporal pattern formation on microdesigned composite catalysts. One of the most significant interaction mechanisms between different reacting domains (consisting of different metal catalysts such as Pt and Rh, coupled through surface diffusion) is the initiation of reaction fronts at the interface between them. We then explore in some detail the effect of two-dimensional composite geometry on this basic building block of composite catalyst dynamics. (c) 2002 American Institute of Physics.     

Construction of entropy solutions for one dimensional elastodynamics via time discretisation

It is shown that the variational approximation scheme for one-dimensional elastodynamics given by time discretisation converges, subsequentially, weakly and a.e. to a weak solution which satisfies the entropy inequalities. We also prove convergence under the restriction of positive spatial derivative (for longitudinal motions).     

A quantitative western blot technique using TMB: Comparison with the conventional technique

Numerous molecular biological experiments performed throughout the world require the detection or quantification of a protein of interest. Western blotting is one of the most popular techniques used for this purpose and offers quantitative information with the aid of specialized software. However, its dependence on the picture that is captured, and the background and the absence of a common protocol prevent the technique from being completely quantitative. To overcome these obstacles, we present a simple and reliable assay that is similar to the regular technique, with the exception of the last stage of band visualization and quantification. We propose that small pieces of the blot that include the protein of interest can be cut and dipped in a small volume of 3,3',5,5'-tetramethylbenzidine solution, giving a colorimetric signal with linear dependence on the quantity of the protein. The reaction is stopped with H₂SO₄, and the signal is measured in a plate reader. This modification shows high linearity without additional costs and can be applied for both purified proteins and proteins found in a lysate. The results obtained with our proposed technique were compared with those obtained by the conventional method and proved to be more reliable.     

On the Hamiltonian structure of the planar steady water-wave problem with vorticity

We consider the stream-function formulation of the hydrodynamic problem for steady rotational water waves both with and without surface tension. A natural Lagrangian formulation is presented from which (different) Hamiltonian formulations for the two cases are derived by duality theory in the spirit of the Legendre–Fenchel transform. The treatment is systematic and clarifies a recent ad hoc approach by Kozlov and Kuznetsov [7].     

Vibration quenching in a large scale rotor-bearing system using journal bearings with variable geometry

In large scale rotating machinery the resonance amplitude during the passage through resonance is a matter of consideration because of its influence in the surrounding environment of the rotational system and foundation. In this paper, a variable geometry journal bearing (VGJB), recently patented, is applied for the mounting of a large scale rotor bearing system operating at the range of medium speed. The simulation of the rotor-bearing system incorporates a recent method for simulation of a multi-segment continuous rotor in combination with nonlinear bearing forces. The use of the current bearing gives results that encourage the use of such a bearing in rotating machinery since the vibration amplitude during the passage through the critical speed can be reduced up to 60–70%. In the presented study, the developed amplitude and the rotor stresses are severely reduced compared to those of the system with normal cylindrical journal bearings during a virtual start up of the system.     

Some combinatorial principles for trees and applications to tree families in Banach spaces

Suppose that is a normalized family in a Banach space indexed by the dyadic tree S. Using Stern's combinatorial theorem we extend important results from sequences in Banach spaces to tree‐families. More precisely, assuming that for any infinite chain β of S the sequence is weakly null, we prove that there exists a subtree T of S such that for any infinite chain β of T the sequence is nearly (resp., convexly) unconditional. In the case where is a family of continuous functions, under some additional assumptions, we prove the existence of a subtree T of S such that for any infinite chain β of T, the sequence is unconditional. Finally, in the more general setting where for any chain β, is a Schauder basic sequence, we obtain a dichotomy result concerning the semi‐boundedly completeness of the sequences .