Ultrabright supramolecular beacons based on the self-assembly of two-photon chromophores on metal nanoparticles

Silver nanoparticles coated with a self-assembled layer of approximately 2500 chromophoric alkylthiol ligands, that exhibit a huge per particle two-photon absorption cross section (2.7 x 10-45 cm4 s photon-1) and a high fluorescence quantum yield (0.33), are reported. Polyfunctionalized variants of these nanoparticles have been produced that show reasonable solubility in water/ethanol mixtures. By virtue of the large number of tethered chromophores, these particles act as strongly two-photon absorbing nanobeacons and may have applications in fluorescence imaging and sensing.     

FTIR-ATR characterization of langmuir-blodgett assemblies of 1-palmitoyl-2-pyrenedecanoylphosphatidylcholine and dipalmitoylphosphatidylcholine

Langmuir-Blodgett assemblies of 1-palmitoyl-2-pyrenedecanoylphosphatidylcholine and dipalmitoylphosphatidylcholine were transferred from an air/water interface onto germanium or silicon attenuated total reflection (ATR) crystals and were investigated by Fourier transform infrared spectroscopy. A detailed attention has been paid to optimize the deposition conditions and to study the organization of transferred mono- and multimolecular layers.     

Optimal Control of Continuous Casting by Nondifferentiable Multiobjective Optimization

A new version of an interactive NIMBUS method for nondifferentiable multiobjective optimization is described. It is based on the reference point idea and the classification of the objective functions. The original problem is transformed into a single objective form according to the classification information. NIMBUS has been designed especially to be able to handle complicated real-life problems in a user-friendly way.The NIMBUS method is used for solving an optimal control problem related to the continuous casting of steel. The main goal is to minimize the defects in the final product. Conflicting objective functions are constructed according to certain metallurgical criteria and some technological constraints. Due to the phase changes during the cooling process there exist discontinuities in the derivative of the temperature distribution. Thus, the problem is nondifferentiable.Like many real-life problems, the casting model is large and complicated and numerically demanding. NIMBUS provides an efficient way of handling the difficulties and, at the same time, aids the user in finding a satisficing solution. In the end, some numerical experiments are reported and compared with earlier results.     

Specification of a query language by the attribute method

Data base applications are large and complex in nature. Therefore we need effective tools to manage complexity in developing data base software. In this paper we demonstrate how the attribute method can be used as a systematic approach to specify software in the data area. We have a relationally complete query language as the specification subject. In data base applications it is important to specify precisely both the semantics of software and constraints related to data base structures and to data base operations. For the former purpose we definesemantic attributes and for the latterchecking attributes.     

Leaky photorefractive surface waves in Bi12TiO20 and Bi12SiO20 crystals

Consistent experimental and numerical simulation studies of photorefractive surface wave propagation in Bi₁₂TiO₂₀ and Bi₁₂SiO₂₀ crystals are presented. We induce the photorefractive surface wave with a Gaussian beam of small diameter and show that light leakage from the surface wave takes the form of multiple beam reflection from the crystal surface. The efficiency of surface wave excitation is proved to be much higher for the divergent Gaussian beam than for the convergent one.     

Large Deviations from the Almost Everywhere Central Limit Theorem

We prove large deviation principles for the almost everywhere central limit theorem, assuming that the i.i.d. summands have finite moments of all orders. The level 3 rate function is a specific entropy relative to Wiener measure and the level 2 rate the Donsker-Varadhan entropy of the Ornstein-Uhlenbeck process. In particular, the rate functions are independent of the particular distribution of the i.i.d. process under study. We deduce these results from a large deviation theory for Brownian motion via Skorokhod's representation of random walk as Brownian motion evaluated at random times. The results for Brownian motion come from the well-known large deviation theory of the Ornstein-Uhlenbeck process, by a mapping between the two processes.     

Some problems in automatic process grouping and file consolidation

The purpose of this paper is to define the operations for process grouping and file consolidation, and also the circumstances under which these operations can be applied, with sufficient accuracy so that they could be performed by a computer program used for system design. The usual consolidation of standing files is made in three steps, using precise matrix operations. Concerning the problem of losing many possibilities for later process grouping when consolidating standing files, two solutions are given. The first uses a matrix, which gives information about the relations between the different update versions of the same file. In the second a matrix is used, which gives information about the precedence relations caused by the original relations of the system, to indicate when the change of the execution order of two processes is possible.     

Spectral Estimates for Two-Dimensional Schrödinger Operators with Application to Quantum Layers

A logarithmic type Lieb-Thirring inequality for two-dimensional Schrödinger operators is established. The result is applied to prove spectral estimates on trapped modes in quantum layers.