Infrared sea surface emissivity including multiple reflection effect for isotropic Gaussian slope distribution model

A method is described for incorporating surface-emitted surface-reflected (SESR) radiation into the calculation of infrared sea surface emissivity. Firstly, the direct emissivity is obtained by ignoring SESR emission. Next, the first order SESR emissivity is obtained by using the direct emission as a radiation source. Finally, the ith order SESR emissivity is iteratively obtained by using the i − 1st order SESR emission.Computational results are in good agreement with a Monte Carlo calculation, where the SESR emissivity increases from an emission angle of 50° showing a maximum value of about 0.03 at an emission angle of 80°. The direct emissivity is smaller than the measured emissivity by 0.02∼0.03 around a wavelength of 10 μm at an emission angle of 73.5°. By incorporating the SESR emission into the emissivity model, the discrepancy between the computed and the measured emissivity is significantly reduced.The advantage of the present method over the previous works is that we need not to specify a cutoff angle to differentiate the radiation from the sea and that from the sky for calculating SESR emission. Instead of using a cutoff angle, the probability that radiation originates from the sea is derived from the probability distribution function of sea surface slope. As a result, the uncertainty in the computation of sea surface emissivity attributed to the uncertainty in cutoff angle could be effectively suppressed.     

Acoustic surface-wave filters without apodisation loss with electrodes with inclined apodisation

The letter reports a new apodisation of electrodes which provides surface-acoustic-wave filters capable of operation without apodisation loss and with sufficiently large stopband attenuation. The effectiveness of the apodisation was shown by experiments.     

A single oral administration of conjugated linoleic acid enhanced energy metabolism in mice

We investigated the effect of a single oral administration of conjugated linoleic acid (CLA) on energy metabolism in mice. Male Std ddY mice were orally administered CLA (5 mL/kg weight) or linoleic acid (5 mL/kg weight) (both solutions at concentrations of 73.5%) as a control. Oxygen consumption was significantly greater in the CLA-administered mice than in the control mice. Respiratory quotient was slightly lower in the CLA-administered mice than in the control mice. We calculated fat and carbohydrate oxidation from oxygen consumption and respiratory quotient. Fat oxidation in the CLA-administered mice was significantly higher than in the control mice, and there was no difference in carbohydrate oxidation. Serum concentrations of noradrenalin and adrenalin in the CLA administered mice were significantly higher than in the control mice. These results suggested that CLA enhanced sympathetic nervous activity and energy metabolism.     

Functional glucosylation of kojic acid and daidzein with the Eucalyptus membrane-associated UDP-glucosyltransferase reaction system

Kojic acid was glucosylated to kojic acid 5- and 7-O-beta-D-glucopyranosides by cultured cells of Eucalyptus perriniana. The glucosylation was also performed effectively by the enzymatic reaction system using membrane-associated UDP-glucosyltransferase from the cells with addition of UDP-glucose. The production of the 5-O-D-glucoside occurred exclusively prior to that of the 7-O-glucoside in both systems. In the same manner, daidzein was converted to daidzin (daidzein 7-O-beta-D-glucopyranoside) by the enzymatic system. Here, we propose methods for the structural modification of phytoestrogen-related substances by enzymatic beta-glucosylation.     

On one- and two-parameter analyses of short fatigue crack growth

Recent data on short fatigue crack growth in two cast and hot isostatically pressed (hipped) aluminum alloys obtained by Shyam, Allison and Jones have been analyzed in terms of a previously proposed one-parameter short crack model which includes consideration of elastic–plastic effects, the Kitagawa effect and the development of crack closure in the wake of a newly formed crack. The material constants obtained in a prior investigation of short crack growth behavior in a cast aluminum alloy tested under fully reversed loading were used as a basis for the present analysis. The predicted rates of fatigue crack propagation are in accord with the experimental results. In the discussion, aspects of the two-parameter approach presented by Shyam et al. are compared with those of the one-parameter method of analysis used herein.     

Investigation of gas-liquid interface in atmospheric-pressure micro plasma with solution

An atmospheric-pressure glow-discharge micro plasma in contact with liquid paraffin is stably generated by using a capacitively coupled plasma method with a mesh electrode. When characteristics of the plasma are measured in the boundary between the micro plasma (gas-phase) and liquid paraffin (liquid-phase) using optical emission spectroscopy, spectrum peaks of the emission of CH and C₂ which dissociate from paraffin are observed. The result indicates that solution can feed particles to the plasma at gas-liquid interface and this plasma is accordingly expected to promote an attractive plasma process for creating materials consisting of elements in various solutions.     

Reliability of AllnAs/lnGaAs/lnP HEMT with WSi ohmic contacts

We have investigated the degradation mechanism of Al_0.48In_0.52As/In_0.53Ga_0.47As/ InP high electron mobility transistors (HEMTs) using WSi ohmic electrodes. Cross-sectional transmission electron microscopy (TEM) observation and en-ergy dispersive x-ray (EDX) analysis reveal impurities diffusion of gate electrode (titanium: Ti) and fluorine (F) in the AlInAs layer after a high temperature (T_a = 170°C operating life test for 500 h. The decrease of drain current (I_ds) during life test shows linear dependence on square root of aging time. It suggests that the degradation is controlled by a diffusion mechanism. Hence, the estimated degradation mechanism of this device is related with decrease of carrier concentration in the epitaxial layer by these diffused impurities. On the other hand, TEM and EDX show no degradation of WSi/InGaAs interface after aging. Therefore, the WSi electrode for this type of HEMT demonstrates excellent high stability under the accelerated operating life test.     

Magnetic field analysis of a 70‐MW‐class superconducting generator by the 3D finite element method

The three‐dimensional magnetic field and eddy current distribution of the 70‐MW‐class superconducting generator was calculated by a finite element method. The condition for the exciting armature coil was calculated by the jω‐method. In the magnetic flux distribution of the armature winding bore, the value obtained by analysis had good agreement with the measurement. An analysis that let the rotor move by the synchronizing speed was also done. The armature voltage for the nonload condition and the armature current for the three‐phase short‐circuit condition obtained by calculations had good agreement with the measurements. The validity of the analytical model for three‐dimensional magnetic field analysis of superconducting generators was confirmed from these results. In addition, the synchronous reactances were calculated using these results with eddy current in the facing. It was found that the facing had the effect of decreasing synchronous reactance by about 5%. © 2000 Scripta Technica, Electr Eng Jpn, 134(2): 53–60, 2001