Fibre optic sensors

Fibre optic sensors represent a considerable advance over traditional optical sensors. They do not require an optical free path and have a better resistance to electromagnetic and temperature variations. They are also smaller and cheaper than their predecessors.     

Comments on “isothermal sustained oscillations in a very simple surface reaction” by C.G. Takoudis,L.D. Schmidt and R. Aris

The oscillating CO oxidation on Pt is examined as a possible candidate for the Takoudis, Schmidt and Aris (TSA) model. Moreover the results of our Monte Carlo simulation of this model reaction are tentatively compared to TSA numerical results.     

Synthesis of selenolates from stannyl and silyl alkylselenides

Stannyl and silyl alkylselenides have been efficiently transformed to the corresponding alkylselenolates on reaction with butyllithiums. Other conditions proved to be limited.     

Three-component synthesis of benzo[b][1,5]thiazepines via coupling–addition–cyclocondensation sequence

2,4-Disubstituted benzo[b][1,5]thiazepines represent nonfluorescent intense yellow chromophores and are readily synthesized from acid chlorides, terminal alkynes, and ortho-amino thiophenols by a consecutive one-pot three-component Sonogashira coupling–Michael addition–cyclocondensation sequence under mild conditions in good yields.     

Optimal L ∞-Error Estimate of a Finite Element Method for Hamilton–Jacobi–Bellman Equations

This paper is concerned with the piecewise linear finite element approximation of Hamilton–Jacobi–Bellman equations. We establish the optimal L ^∞-error estimate, combining the concepts of subsolution and discrete regularity.     

Decomposing torsion modules

E. Matlis proved that if R is an integral domain with quotient field Q and K is the R-module Q/R, then all torsion R-modules decompose into a direct sum of local submodules if and only if K decomposes into a direct sum of local submodules. Thus K is a test module to determine whether torsion modules decompose. We generalize this result to commutative rings. If R is a commutative ring and a torsion theory of R is given by a Gabriel topology , then form the ring of quotients R_ and let K be the cokernel of the canonical ring homomorphism from R to R_. In some special cases, every -torsion R-module decomposes into a direct sum of local submodules if and only if K decomposes. However, there is an example where this is not the case. The principal result is: given R,  and K, there is a related filter _K of ideals of R, which is a subset of , such that all _K-pretorsion R-modules decompose into a direct sum of local submodules if and only if K decomposes. The relationship between  and _K is investigated.