Molecule without electrons: binding bare nuclei with strong laser fields

We show how a carefully chosen combination of strong linearly and circularly polarized laser fields can bind two same-sign charges, not only suppressing their Coulomb repulsion in all three spatial dimensions, but also creating an effective attraction. As an example, we show how a molecule HD2+ stripped of both electrons can be kept bound by the laser fields.     

Characterization by radiotracer of flow dynamics in laboratory and pilot-plant molecular sieves columns dehydrating organic liquids

Experiments with^113mIn radiotracer in 0.01M aqueous solutions of EDTA have been carried out to investigate the fluid flow dynamics in columns of three different diameters filled with molecular sieve spherical particles. The dependence of the Peclet number upon the column diameter-to-particle diameter ratio is demonstrated and irregularities and fluctuations for ratios smaller than 10 are observed. The influence of these phenomena on the adsorption process was investigated.     

Factorization strategies for third-order tensors

Operations with tensors, or multiway arrays, have become increasingly prevalent in recent years. Traditionally, tensors are represented or decomposed as a sum of rank-1 outer products using either the CANDECOMP/PARAFAC (CP) or the Tucker models, or some variation thereof. Such decompositions are motivated by specific applications where the goal is to find an approximate such representation for a given multiway array. The specifics of the approximate representation (such as how many terms to use in the sum, orthogonality constraints, etc.) depend on the application.In this paper, we explore an alternate representation of tensors which shows promise with respect to the tensor approximation problem. Reminiscent of matrix factorizations, we present a new factorization of a tensor as a product of tensors. To derive the new factorization, we define a closed multiplication operation between tensors. A major motivation for considering this new type of tensor multiplication is to devise new types of factorizations for tensors which can then be used in applications.Specifically, this new multiplication allows us to introduce concepts such as tensor transpose, inverse, and identity, which lead to the notion of an orthogonal tensor. The multiplication also gives rise to a linear operator, and the null space of the resulting operator is identified. We extend the concept of outer products of vectors to outer products of matrices. All derivations are presented for third-order tensors. However, they can be easily extended to the order-p(p>3) case. We conclude with an application in image deblurring.     

Functional equation helps in finding affine-covariant probability distributions

To select variables which provide the most relevant clustering, researchers use a probability density f that depends on the means E and the covariance matrix C of the data. Under the assumption that the distributions are normal, this density becomes proportional to f(C) = |det(C)| ^α for some real value α, where det(C) is the determinant of the matrix C. This function is affine-covariant in the sense that the ratios of the two density values do not change under an arbitrary affine transformation. In this paper, we show that only the functions f(C) = |det(C)| ^α satisfy the functional equation

Spectral theory and interpolation of operators

Let (B⁰, B¹) be an interpolation pair of Banach spaces, and let T: B^j → B^j be a bounded linear operator, j = 0, 1. We study the spectrum of T on an intermediate space B. In essence, it is shown that this spectrum depends only on the interpolation properties of B.     

Experimental investigation of wall temperature evolution in a compact heat exchanger at a drastic change in the heat flux

Results of experimental study of the nonstationary temperature field on the surface of a complex shape channel at a jump-like change in heat release with time in the wall of packing with one-way heat supply are presented. Measurements were carried out in the air flow between two plates with triangular corrugations directed at 90° relative each other. Measurements were carried out by thermocouples with the thickness of less than 10 microns. The effect of Reynolds number and supplied power on the temperature change over the heat exchanger surface with time caused by a jump-like change in supplied electric power at a turbulent air flow is analyzed. Investigations have revealed typical features of temperature evolution over the perimeter of the heated cell. Experimental data on time dependence of temperature can be approximated well by the exponential function.     

Spatial structure of the flow in a channel with corrugated wall

Results of visual studies of the flow structure of the air jet in a channel with corrugated wall are presented. The studies have been carried out in the laminar and turbulent flows. The typical large-scale structures and zones of intensive turbulent mixing have been determined in the flow. The general scheme of the flow is suggested.