Fabrication of glass-capsuled CdTe microcrystals using laser evaporation and plasma chemical vapour deposition method

CdTe microcrystals encapsulated in a silica glass layer were successfully fabricated. Spherical CdTe microcrystals were prepared by laser evaporation of a CdTe target in an argon gas atmosphere. The ensuing microcrystals plus argon gas passed through a tetramethoxysilane (TMOS)+O₂ plasma in which they were encapsulated in an amorphous layer, 2–2.5 nm thick. Characteristic X-rays from the surface layer were measured using an energy dispersive X-ray spectrometer equipped in a high-resolution transmission electron microscope. Measurements indicated that the glass layer consisted of silicon and oxygen, with no cadmium or tellurium included. The CdTe microcrystals fabricated with our laser evaporation system showed two specific kinds of particle: small particles (below 10 nm) and large ones (over 100 nm). Using precise electron-beam diffraction testing, we concluded that the large microcrystal is a single crystal with a hexagonal structure. The deposition rates and infrared transmission of silica glass prepared by TMOS or tetraethoxysilane plasma-enhanced chemical vapour deposition are also discussed. The highest deposition rate, 30 nm s^–1, of silica glass can be achieved in the centre of the plasma when the input r.f. power is 150 W.     

Theoretical study of NO decomposition on Cu-ZSM-5 catalyst models

The decomposition mechanism of NO on Cu-ZSM-5 catalyst models was investigated using ab initio molecular orbital calculations with Huzinaga's MIDI-P basis set [see S. Huzinaga, Gaussian Basic Sets for Molecular Calculations, Elsevier, Amsterdam, 1984]. Two reaction routes were assumed for each model and the geometry of all molecules was optimized.     

Smart optical receiver with automatic decision threshold settingand retiming phase alignment

The requirements for a smart optical receiver are discussed, and a design architecture suitable for introducing ICs based on automatic decision threshold setting and retiming phase alignment using digital/analog signal processing feedback is proposed. With the proposed architecture, the decision threshold level and the retiming clock phase of received data in the decision circuit are automatically adjusted to the optimum position. This obviates the need for decision threshold level and retiming clock phase adjustments in production testing, and it reduces the power penalty (receiver sensitivity degradation) on the received optical waveform variation. The power penalty caused by temperature and supply-voltage variations and aging in installation is also reduced. The performance of the proposed architecture is estimated; the power penalty as compared with the manual optimum adjustment is less than 0.4 dB, and the robustness to avalanche photodiode multiplication factor variations and crosstalk are improved     

Pulmonary gas exchange function of supine elderly subjects, in relation to closing volumes (author''s transl)]

13 New 3-aryl-5-benzylidene-2-thiohydantoins were obtained by condensation of 3-o-tolyl- and 3-m-to?yl-2--thiohydantoin with aromatic aldehydes. The structure of the obtained compounds was confirmed by IR spectra. Derivatives of 2-thiohydantoin 1-13 show weak anticonvulsant activity in pentetrazole test and show no protecting activity against the maximal electric shock.     

Novel Polarimetric Technique Exploring Spatiotemporal Birefringent Response of an Anti-ferroelectric Liquid Crystal Cell

Abstract

This paper describes a novel polarimetric technique for mapping the spatiotemporal birefringent parameters characterizing an anti-ferroelectric liquid crystal cell. A linearly polarized beam of light transmitted by the liquid crystal cell turns into an elliptically polarized beam. Some birefringent irregularities existing over the cell make state of polarization of the elliptically polarized beam of light be spatiotemporal. This beam works as a signal beam to interfere with a reference beam consisting of two orthogonal linearly polarized components. The resultant interference pattern is taken by a charge-coupled device video camera and recorded in a computer. The computer gives the information required for determining the spatiotemporal birefringent parameters that characterize the liquid crystal cell. The major advantage is that the two-dimensional distribution of the birefringent axes as well as the two principal refractive indices can be determined simultaneously, and no use of any optical components for polarization alignment makes it possible to follow a rapid change in birefringent parameters within the maximum frame rate of the video camera. A change in time-dependent birefringent parameter is measured at every 0·1 ms for the demonstration experiment.     

Investigation of the cause of peculiar irradiation behavior of 9Cr-ODS steel in BOR-60 irradiation tests

Four experimental fuel assemblies (EFAs) containing 9Cr-ODS steel cladding fuel pins were previously irradiated in the BOR-60 to demonstrate the in-reactor performance of 9Cr-ODS steel for use as fuel cladding tubes. One of the EFAs achieved the best data, a peak burn-up of 11.9at% and a neutron dose of 51 dpa, without any microstructure instability or any fuel pin rupture. On the other hand, in another EFA (peak burn-up, 10.5at%; peak neutron dose, 44 dpa), peculiar irradiation behaviors, such as microstructure instability and fuel pin rupture, occurred. Investigations of the cause of these peculiar irradiation behaviors were carried out. The detection sensitivity in an ultrasonic inspection test was shown to be low for the metallic Cr and metallic Fe inclusions. The peculiar microstructure change reappeared with high-temperature thermal-aging of the 9Cr-ODS steel containing metallic Cr inclusions. The strength and ductility of the defective part containing metallic Cr inclusions were appreciably lower than those of a standard part without the inclusions. The combined effects of matrix Cr heterogeneity (presence of metallic Cr inclusions) and high-temperature irradiation were concluded to be the main cause of the peculiar microstructure change in 9Cr-ODS steel cladding tubes in the BOR-60 irradiation tests. They contributed to the fuel pin rupture.     

Phase-interpolated averaging for analyzing electroencephalography and magnetoencephalography epochs

Stimulus-locked averages of electroencephalography (EEG) and magnetoencephalography (MEG) epochs reveal characteristic waveforms. EEG/MEG generation models to have reconstruct such waveforms have been recently proposed. These models assume that evoked, phase-modulated, and amplitude-modulated activities occur solely or simultaneously. We propose a two-stage stimulus-locked averaging method, called phase-interpolated averaging, to investigate the EEG/MEG generation process. First, virtual EEG/MEG epochs, which would be obtained as if instantaneous phases for each time sampling point were on a phase-grid, are interpolated from actually measured EEG/MEG epochs. Then, the virtual EEG/MEG epochs are discrete Fourier transformed. A simulation revealed that the zeroth Fourier term revealed the evoked activity, the first Fourier term revealed the amplitude-modulated activity, and the condition number of the interpolation reflected the phase-modulated activity. On the basis of these facts, a preliminary EEG analysis implied that the evoked activity is much smaller than what would be expected by using conventional averaging, the evoked and phase-modulated activities simultaneously occur, and the amplitude-modulated activity occasionally associates with the evoked and phase-modulated activities. To the best of our knowledge, this is the first time that these three activities have been shown to coexist by actually separating them.     

Prediction of vortex penetration depth at thermal stratification by cavity flow in a branch pipe with closed end (effect of heat radiation condition on temperature fluctuations)

In a branch pipe with one closed end, the cavity flow penetrates into the branch pipe from the main loop and a thermal boundary layer occurs because the cavity flow is a hot fluid, but heat removal causes a colder fluid in the branch pipe. This thermal stratification may affect the structural integrity. Therefore, a pipe design standard to suppress thermal fatigue should be established. The pipe design standard consists of the maximum penetration depth L_sv and the minimum penetration depth L_sh. In order to establish an evaluation method for L_sh, a visualization test and a temperature fluctuation test were carried out. A theoretical formula for thermal stratification was introduced from the heat balance model. Then the model was used to obtain an empirical equation from the map of fluid temperature fluctuation. This method can predict the vortex penetration depth by cavity flow in horizontal branch pipes. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res, 36(1):38–55, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20135