Microelectromechanical diffraction gratings: Areas of applicability and prospects

The structure and specific features of operation of microelectromechanical systems, micromirror devices, and diffraction gratings controlled by an electric field are considered. Elements of microelectromechanical diffraction gratings and some applied problems solved with the use of these gratings are described. A new element of the microelectromechanical diffraction grating based on using dielectric materials with a high dielectric permeability in the gap between the electrodes is proposed. As compared with available analogs, this element has a lower control voltage, a higher clock frequency, and better processability. The characteristics of the new element and available analogs are compared.     

Cold crucible melting and characterization of titanate-zirconate pyrochlore as a potential rare earth/actinide waste form

La-Ce-Gd titanate-zirconate pyrochlore-based ceramics was synthesized at the lab-scale inductive melting unit with a 56?mm inner diameter cold crucible. Batch feeding rate and melting ratio were 3?kg/h and 3?kW?h/kg respectively. The ceramics is composed of 85–90?vol% zoned grains of the pyrochlore structure phase, the sample has excellent chemical durability in hot water and may be considered as a promising matrix for actinide – rare earth fraction of high level waste.     

Features of the Preparation and Study of Electrophysical Characteristics (BeO+TiO2)-Ceramics by Impedance Spectroscopy

Refractories and Industrial Ceramics - An electrically conducting two-component BeO-ceramic with the addition of micro- and nano-crystalline TiO2 powder is prepared that can be used as a material...     

Vitrification of a surrogate for high-level wastes from the Savannah River plant (USA) on a cold-crucible bench facility

Two experiments on the vitrification of a surrogate for the wastes from the Savannah River plant (USA) have been performed on a cold-crucible (inner diameter 216 mm) induction-melting bench facility at the Moscow Scientific and Industrial Association Radon (1.76 MHz, 60 kW). To obtain borosilicate glasses with two compositions containing 45 mass % oxides of the wastes (computed) a slurry with moisture content about 60 mass % and a mixture of reagents as the glass-forming additives gave a mass velocity of the slip 8 kg/h on average, glass output about 2 kg/h, and specific glass product rate about 47 kg/(m²·h). The specific energy consumption was 20 k·W·h/kg. It was shown that the mass velocity of the slip can be increased to 18 kg/h. Switching to glass-forming additives consisting of the special borosilicate frit-200 and-320 and lowering the water content in the slurry to 25–30 mass % increases the productivity of the process by 15–35%. The specific glass production rate reaches 100 kg/(m²·h). The glasses produced contained a small quantity of a magnetitic spinel phase. __________ Translated from Atomnaya énergiya, Vol. 102, No. 4, pp. 225–232, April, 2007.     

Stark spectroscopy of a probe lithium beam excited with two dye lasers as a technique to study a high-power ion-beam diode

A non-disturbing measurement of electric field distributions is a subject of special interest in plasma physics and high-voltage devices. In this paper we describe a diagnostic technique for remote sensing of electric fields via injection of a probe beam of lithium atoms and cascade excitation of resonance fluorescence with two broadband dye lasers. The fluorescence spectrum was recorded using a monochromator equipped with an optical multi-channel analyser. The magnitude of the local electric field was retrieved from the Stark-shifted components of the 3d-2p lithium spectral line. The technique was applied to measurements of the electric field in the applied-B-field high-voltage diode of the 1 TW KALIF ion-beam accelerator.     

An HCN Interferometer for Measuring the Electron Density Distribution in the Plasma of the Л-2M Stellarator

A diagnostic setup for determining the electron density profile in the plasma of the -2M stellarator is described. An interferometer based on an HCN laser (337 m) with a mirror in a vacuum chamber and built according to the Michelson scheme is the main element of the setup. To translate the phase shift to a frequency range convenient for recording, a system with a mechanical frequency shifter based on the Doppler effect is used. InSb photoresistors cooled with liquid helium are used as radiation detectors. Seven mirrors are arranged in the vacuum chamber. Any of these can be included in the optical system of the interferometer by rotating an external mirror; scanning along seven chords is thus accomplished. The results are recorded in digital form. The subsequent data processing makes it possible to determine the parameters of the spatial density distribution functions belonging to an a priori selected family.     

Identification of Spiro-Fused [3-azabicyclo[3.1.0]hexane]oxindoles as Potential Antitumor Agents: Initial In Vitro Evaluation of Anti-Proliferative Effect and Actin Cytoskeleton Transformation in 3T3 and 3T3-SV40 Fibroblast

Novel heterocyclic compounds containing 3-spiro[3-azabicyclo[3.1.0]hexane]oxindole framework (4a, 4b and 4c) have been studied as potential antitumor agents. The in silico ADMET (adsorption, distribution, metabolism, excretion and toxicity) analysis was performed on 4a–c compounds with promising antiproliferative activity, previously synthetized and screened against human erythroleukemic cell line K562 tumor cell line. Cytotoxicity of 4a–c against murine fibroblast 3T3 and SV-40 transformed murine fibroblast 3T3-SV40 cell lines were evaluated. The 4a and 4c compounds were cytotoxic against 3T3-SV40 cells in comparison with those of 3T3. In agreement with the DNA cytometry studies, the tested compounds have achieved significant cell-cycle perturbation with higher accumulation of cells in G0/G1 phase. Using confocal microscopy, we found that with 4a and 4c treatment of 3T3 cells, actin filaments disappeared, and granular actin was distributed diffusely in the cytoplasm in 82–97% of cells. The number of 3T3-SV40 cells with stress fibers increased to 7–30% against 2% in control. We discovered that transformed 3T3-SV40 cells after treatment with compounds 4a and 4c significantly reduced the number of cells with filopodium-like membrane protrusions (from 86 % in control cells to 6–18% after treatment), which indirectly suggests a decrease in cell motility. We can conclude that the studied compounds 4a and 4c have a cytostatic effect, which can lead to a decrease in the number of filopodium-like membrane protrusions.