The radiation of polarized matter in a coaxial wave-guide of general cross-section

The electromagnetic field in a coaxial wave-guide of general cross-section is derived. The transversal electromagnetic mode and the corresponding energy flow are especially investigated.     

Gamma-radiation of193Au

The gamma-radiation of¹⁹³Au has been studied by means of a Ge(Li) semiconductor detector. In addition to the transitions observed by Svahn et. al. (Z. Physik210 (1968), 466), 21 new transitions have been found. With the use of the relative conversion line intensities from the above reference and the -ray intensities of this work, the number of internal conversion coefficients _K has been determined. The multipolarities of the transitions have been deduced from a comparison of the experimental and theoretical _K -values. Some additions to the¹⁹³Au decay scheme were made on the basis of new experimental results.     

Charged ±2π-twist Disclinations in Ferroelectric Liquid Crystals

The electrostatic charge of (±2)-twist disclinations in ferroelectric chiral smectic C liquid crystals is introduced as an approximation in order to simplify the evaluation of the electrostatic self-energy of disclination. As an example, electrostatic charges of (±2)-twist disclinations in an infinite sample are evaluated. Screening effects of free charges in a material and of the ferroelectric structure surrounding the disclination are taken into account by introducing a phenomenological depolarization factor.     

Simulation of the thermal radiation effect of an arc on polymer walls in low-voltage circuit breakers

A model of sputtering (ablation) of polymer walls caused by the thermal effect of an arc in low-voltage circuit breaker is suggested. The model takes into account heating, volume thermal decomposition, and fusion of the polymer, as well as the screening action of the vapor from the surface. The ablation of the walls is due to the UV component of the arc radiation, most of which is absorbed in the vapor. It is shown that the ablation conditions change drastically with distance to the center of the arc. The parameters of the reaction zone and of the area occupied by the melted polymer are estimated.     

Cell-specific and nuclear targeting with [M(CO)(3)](+) (M=(99m)Tc, Re)-based complexes conjugated to acridine orange and bombesin

Receptor-specific nuclear targeting requires trifunctional metal complexes. We have synthesized [M(L(2)-pept)(L(1)-acr)(CO)(3)] (pept=peptide; acr=acridine-based agent) in which the fac-[M(CO)(3)](+) moiety (1st function, M=(99m)Tc, Re) couples an acridine-based nuclear-targeting agent (2nd function, L(1)-acr) and the specific cell-receptor-binding peptide bombesin (3rd function, L(2)-pept). The metal-mediated coupling is based on the mixed ligand [2+1] principle. The nuclear targeting agents have been derivatised with an isocyanide group for monodentate (L(1)) and bombesin (BBN) with a bidentate ligand (L(2)) for complexation to fac-[M(CO)(3)](+). For nuclear uptake studies, the model complexes [Re(L(2))(L(1)-acr)(CO)(3)] (L(2)=pyridine-2-carboxylic acid and pyridine-2,4-dicarboxylic acid) were synthesized and structurally characterized. We selected acridine derivatives as nuclear-targeting agents, because they are very good nucleus-staining agents and exhibit strong fluorescence. Despite the bulky metal complexes attached to acridine, all [Re(L(2))(L(1)-acr)(CO)(3)] showed high accumulation in the nuclei of PC3 and B16F1 cells, as evidenced by fluorescence microscopy. For radiopharmaceutical purposes, the (99m)Tc analogues have been prepared and radioactivity distribution confirmed the fluorescence results. Coupling of BBN to L(2) gave the receptor-selective complexes [M(L(2)-BBN)(L(1)-acr)(CO)(3)]. Whereas no internalization was found with B16F1 cells, fluorescence microscopy on PC3 cells bearing the BBN receptor showed high and rapid uptake by receptor-mediated endocytosis into the cytoplasm, but not into the nucleus.     

59Ni and 63Ni separation from boric acid concentrates produced at NPP

Procedure for direct separation of radionickel from boric acid concentrate was developed. Quantitative separation from 100 mL of real concentrate on the column filled with 3 mL of PAN-DMG composite material was achieved. PAN-DMG material (dimethylglyoxime in porous beads of polyacrylonitrile) was compared with Ni Resin and DMG-PAN material exhibited higher sorption capacity for nickel than Ni Resin.     

Production of picosecond, kilojoule, and petawatt laser pulses via Raman amplification of nanosecond pulses

Raman amplification in plasma has been promoted as a means of compressing picosecond optical laser pulses to femtosecond duration to explore the intensity frontier. Here we show for the first time that it can be used, with equal success, to compress laser pulses from nanosecond to picosecond duration. Simulations show up to 60% energy transfer from pump pulse to probe pulse, implying that multikilojoule ultraviolet petawatt laser pulses can be produced using this scheme. This has important consequences for the demonstration of fast-ignition inertial confinement fusion.     

Numerische Berechnung des Partikeltransportes zu einer laminar angeströmten Kreisscheibe

Increasingly process steps become important, in which particles as product particles or contaminants are deposited on substrates out of the gas phase. In this paper the particles transport processes are investigated close to the surface of a circular plate surrounded by a laminar flow. The analogy between the governing equations of momentum, energy and mass is applied to the extended diffusion equation. In the nondimensional form the results of the numerical calculations give informations about velocity, temperature and particle concentration boundary layer thickness as well as their distributions. Especially the impact of external forces on particle concentration boundary layer thickness and profile is discussed. The transport of submicron particles to the surface due to convection, diffusion, gravity and thermophoretic forces acting independently is investigated. In the used normalized form the different forces are acting as one resulting force independently of their origin. Their resulting effect in comparison to the effect due to convective diffusive transport is important for particle deposition.     

Surface disclination cores in the B2 phase of bent-shaped molecules described by the Peierls–Nabarro model

The Peierls–Nabarro model, originally proposed to describe dislocation core in solids, is used to model core structures of 2π- and π-surface disclinations in the B₂ phase of bent-shaped molecules. Structures of disclination cores are determined by surface anchoring. Core parameters as core widths (and positions of two partial π-disclinations as parts comprising 2π-disclination) are estimated using surface anchoring energy. Disclination core widths are usually narrow for strong anchoring. In such a case they are barely observable; nevertheless, they can exist.