Elastic scattering of electrons from tetrahydrofuran molecule

Absolute differential cross-sections (DCSs) for elastic scattering of electrons from the DNA backbone sugarlike analogue tetrahydrofuran (THF) molecule were determined using a crossed beam measurements for incident energies from 20 eV to 300 eV and scattering angles from 10^o to 110^o. Using the relative-flow technique, elastic DCSs for THF relative to nitrogen have been obtained at incident energies of 20, 30, 40, 50 and 60 eV. In the energy region above 30 eV, the DCSs were measured independently as a function of both incident electron energy and scattering angle. Therefore, this set of relative DCSs has been calibrated to the absolute scale via normalization to a single point in the overlapping region. Additionally, both vibrational and electronic energy loss spectra for THF are presented and influence of energy resolution to the obtained DCSs is discussed.     

Dependence of Total p-Electron Energy on the Number of Non-Bonding Molecular Orbitals

In recent work [Gutman et al. (2004) Chem Phys Lett 383: 171] a method was developed by means of which the influence of non-bonding molecular orbitals (NBMOs) on the value of total -electron energy (E) can be separated from the multitude of other molecular-structure-dependent effects. We now extend this method and establish the relation between E and the number n ₀ of NBMOs. It is shown that E (when computed within the HMO approximation, and expressed in the units of the HMO resonance integral ) is a decreasing function of n ₀, and that the dependence of E on n ₀ is almost perfectly linear.     

Electrochemical Characterization of the Interaction of Multiwalled Carbon Nanotubes with Doxorubicin

It has been suggested that multiwalled carbon nanotubes (MWCNTs) interacting with pharmaceutics may be introduced into the body as nanocarriers. To deliver the anticancer drugs, covalent or noncovalent functionalization of MWCNTs is required. In this study, the influence of oxidation on MWCNTs in the interaction with chemotherapeutic drug, doxorubicin, was characterized. The binding of doxorubicin with MWCNTs decreased rapidly with the increasing oxidation period with sulfuric acid. However, with nitric acid, the interaction increased initially and slowly decreased with time. The best results were obtained for sulfuric and nitric acid following 1 and 3?h of oxidation, respectively. The results show that sulfuric acid provided more favorable interaction for MWCNTs with doxorubicin than nitric acid.     

A GPU-based hyperbolic SVD algorithm

A one-sided Jacobi hyperbolic singular value decomposition (HSVD) algorithm, using a massively parallel graphics processing unit (GPU), is developed. The algorithm also serves as the final stage of solving a symmetric indefinite eigenvalue problem. Numerical testing demonstrates the gains in speed and accuracy over sequential and MPI-parallelized variants of similar Jacobi-type HSVD algorithms. Finally, possibilities of hybrid CPU–GPU parallelism are discussed.     

The Kramer–Mesner method with tactical decompositions: some new unitals on 65 points

We propose a combination of two known computational methods for the construction of designs with prescribed groups of automorphisms: the Kramer–Mesner method and the method of tactical decompositions. This combined method is used to construct new unitals with parameters 2‐(65, 5, 1). © 2011 Wiley Periodicals, Inc. J Combin Designs 19:290‐303, 2011     

An alternative approach to solving cost minimization problem with Cobb–Douglas technology

Central European Journal of Operations Research - We propose a new method for solving the production cost minimization problem with Cobb–Douglas technology. The method is based on weighted...     

Electronic states of neutral and ionized tetrahydrofuran studied by VUV spectroscopy and ab initio calculations

The electronic spectroscopy of isolated tetrahydrofuran (THF) in the gas phase has been investigated using high-resolution photoabsorption spectroscopy in the 5.8–10.6 eV with absolute cross-section measurements derived. In addition, an electron energy loss spectrum was recorded at 100 eV and 10° over the 5–11.4 eV range. The He(I) photoelectron spectrum was also collected to quantify ionisation energies in the 9–16.1 eV spectral region. These experiments are supported by the first high-level ab initio calculations performed on the excited states of the neutral molecule and on the ground state of the positive ion. The excellent agreement between the theoretical results and the measurements allows us to solve several discrepancies concerning the electronic state spectroscopy of THF. The present work reconsiders the question of the lowest energy conformers of the molecule and its population distribution at room temperature. Electronic supplementary material  Supplementary Online Material     

Dislocation Transport in Single Crystals and Dislocation-based Micromechanical Hardening

The higher-dimensional kinematical dislocation continuum theory of Hochrainer (2006) and a homogenized version thereof by Hochrainer, Zaiser and Gumbsch (2010) are reviewed. A three-dimensional Finite Element solution of the homogenized theory is presented, interpreted physically and compared to the results of the Geometrically Necessary Dislocations theory. (© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)