303 research outputs found
Optical Absorption and Raman Spectroscopy Study of the Fluorinated Double-Wall Carbon Nanotubes
Double-wall carbon nanotube (DWNT) samples have been fluorinated at room temperature with varied concentration of a fluorinating agent BrF3. Content of the products estimated from X-ray photoelectron data was equal to CF0.20 and CF0.29 in the case of deficit and excess of BrF3. Raman spectroscopy showed considerable decrease of carbon nanotube amount in the fluorinated samples. Analysis of optical absorption spectra measured for pristine and fluorinated DWNT samples revealed a selectivity of carbon nanotube fluorination. Nanotubes with large chiral angle are more inert to the fluorinating agent used
Redescriptions of Ligophorus cephali Rubtsova, Balbuena, Sarabeev, Blasco-Costa & Euzet, 2006 and L. chabaudi Euzet & Suriano, 1977 (Monogenea: Ancyrocephalidae), with notes on the functional morphology of the copulatory organ
Redescriptions of Ligophorus cephali Rubtsova, Balbuena, Sarabeev, Blasco-Costa & Euzet, 2006 and L. chabaudi Euzet & Suriano, 1977 based on original material from the Black Sea, the Mediterranean Sea and the Sea of Japan are presented. A comparison of samples of these two species from different regions was carried out with the aid of principal components analysis. The occurrence of L. chabaudi on Mugil cephalus in the Sea of Japan was confirmed. The functional morphology of the male copulatory organ was examined, and the use of the shape of this structure in the taxonomy of Ligophorus Euzet & Suriano, 1977 is discussed
Redescription of Ligophorus mediterraneus Sarabeev, Balbuena & Euzet, 2005 (Monogenea: Ancyrocephalidae) with some methodological notes
A redescription of Ligophorus mediterraneus Sarabeev, Balbuena & Euzet, 2005, based on original material from the Black and Mediterranean Seas, is presented and new diagnostic characters for its recognition are proposed. The unlikely wide range of variation in the angle between the shaft and point of the anchors, reported for this species and for some others in the genus, is analysed, and the structure of the ventral bar in Ligophorus spp. is described and its taxonomic significance discussed
Brillouin light scattering and second harmonic generation of strontium barium niobate crystals
The Study of the Conformation and Dynamics of the New Quaternary Phosphonium Salts by NMR Spectroscopy
A number of quaternary phosphonium salts on the basis of pyridoxine derivatives were investigated by nuclear magnetic resonance (NMR) spectroscopy methods. Conformational exchange processes for each compound in solution were studied using dynamic NMR experiments. Energy barriers of the conformational transitions were determined. © 2014 Springer-Verlag Wien
Algorithm and performance of a clinical IMRT beam-angle optimization system
This paper describes the algorithm and examines the performance of an IMRT
beam-angle optimization (BAO) system. In this algorithm successive sets of beam
angles are selected from a set of predefined directions using a fast simulated
annealing (FSA) algorithm. An IMRT beam-profile optimization is performed on
each generated set of beams. The IMRT optimization is accelerated by using a
fast dose calculation method that utilizes a precomputed dose kernel. A compact
kernel is constructed for each of the predefined beams prior to starting the
FSA algorithm. The IMRT optimizations during the BAO are then performed using
these kernels in a fast dose calculation engine. This technique allows the IMRT
optimization to be performed more than two orders of magnitude faster than a
similar optimization that uses a convolution dose calculation engine.Comment: Final version that appeared in Phys. Med. Biol. 48 (2003) 3191-3212.
Original EPS figures have been converted to PNG files due to size limi
Dependent coordinates in path integral measure factorization
The transformation of the path integral measure under the reduction procedure
in the dynamical systems with a symmetry is considered. The investigation is
carried out in the case of the Wiener--type path integrals that are used for
description of the diffusion on a smooth compact Riemannian manifold with the
given free isometric action of the compact semisimple unimodular Lie group. The
transformation of the path integral, which factorizes the path integral
measure, is based on the application of the optimal nonlinear filtering
equation from the stochastic theory. The integral relation between the kernels
of the original and reduced semigroup are obtained.Comment: LaTeX2e, 28 page
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