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71.
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73.
An analytical method for the determination of 32 kinds of pesticide residues in onions, Welsh onions and mushrooms using gas chromatograph with an atomic emission detector (GC-AED) was developed. The pesticides were extracted with acetone-n-hexane (2:3) mixture. The crude extract was partitioned between 5% sodium chloride and ethyl acetate-n-hexane (1:4) mixture. The extract was passed through a Florisil mini-column for cleanup with 10 mL of acetone-n-hexane (1:9) mixture. Although the sensitivity of GC-AED was inferior to that of GC-ECD, GC-AED has a superior element-selectivity. Therefore pesticide residues in foods could be analyzed more exactly by using GC-AED. Thirty-two pesticides including chlorine in onion, Welsh onion and shiitake mushroom were detected without interference. Recoveries of these pesticides from samples determined by GC-AED were 64-114%, except for a few pesticides.  相似文献   
74.
Full analysis of triglycerides of natural fats and oils has been investigated by the combination of argentation high performance liquid chromatography (HPLC) with nonaqueous reversed phase (NARP) HPLC. An infrared detector was used in argentation HPLC, because it indicated molar responsibility to all triglycerides. After peak trapping with argentation HPLC, each triglyceride fraction was analyzed with NARP chromatography using the glyceride-selective post-column reactor detector. The results of the analyses of triglycerides of palm oil and cocoa butter by the proposed method agreed well with those reported earlier.  相似文献   
75.
This serial research has proposed the hybrid power system combined the wind power unit with the counter-rotating type pump-turbine unit, to provide the constant output for the grid system, even at the suddenly fluctuating/turbulent wind circumstance. In this paper, the tandem impellers prepared for the counter-rotating type pumping unit were operated at the turbine mode, and the performances and the flow conditions were investigated numerically with accompanying the experimental results. Even though providing the pumping unit for the turbine mode, the maximum hydraulic efficiency is close to one of the counter-rotating type hydroelectric unit designed exclusively for the turbine mode. Besides, the runners/impellers of the unit work evidently so as to coincide the angular momentum change through the front runners/impellers with that through the rear runners/impellers, namely to take the axial flow at not only the inlet but also the outlet, without the guide vanes. From these results, it can be concluded that this type unit is effective to work at not only the pumping but also the turbine modes.  相似文献   
76.
A new experimental technique was developed for detecting structure changes at electrode/electrolyte interface of lithium cell using X-ray reflectometry and two-dimensional model electrodes with a restricted lattice-plane. The electrodes were constructed with an epitaxial film of LiCoO2 synthesized by pulsed laser deposition method. The orientation of the epitaxial film depends on the substrate plane; the 2D layer of LiCoO2 is parallel to the SrTiO3 (1 1 1) substrate ((003)LiCoO2//(111)SrTiO3)((003)LiCoO2//(111)SrTiO3), while the 2D layer is perpendicular to the SrTiO3 (1 1 0) substrate ((110)LiCoO2//(110)SrTiO3)((110)LiCoO2//(110)SrTiO3). The anisotropic properties were confirmed by electrochemical measurements. Ex situ X-ray reflectivity measurements indicated that the impurity layer existed on the as-grown LiCoO2 was dissolved and a new SEI layer with lower density was formed after soaking into the electrolyte. In situ X-ray reflectivity measurements indicated that the surface roughness of the intercalation (1 1 0) plane increased with applying voltages, while no significant changes in surface morphology were observed for the intercalation non-active (0 0 3) plane during the pristine stage of the charge–discharge process.  相似文献   
77.
The rainbow schlieren deflectometry has been combined with the computed tomography to obtain three-dimensional density fields of shock containing free jets and we call the method the schlieren CT. Experiments on the schlieren CT have been performed at a nozzle pressure ratio of 4.0 by using an axisymmetric convergent nozzle with an inner diameter of 10 mm at the exit where the nozzle was operated at an underexpanded condition. Multidirectional rainbow schlieren pictures of an underexpanded sonic jet can be acquired by rotating the nozzle about its longitudinal axis in equal angular intervals and the three-dimensional density fields are reconstructed by the schlieren CT. The validity of the schlieren CT is verified by a comparison with the density fields reconstructed by the Abel inversion method. As a result, it is found that excellent quantitative agreement is reached between the three-dimensional jet density fields reconstructed from both methods.  相似文献   
78.
The accelerator-driven transmutation system has been studied at the Japan Atomic Energy Research Institute. This system is a hydrid system which consists of a high intensity accelerator, a spallation target and a subcritical core region. In the conceptual design study, two types of system concepts, sodium cooled and lead-bismuth cooled system, are being studied. In this study, we fucus on our lead-bismuth cooled accelerator-driven transmutation system to investigate basic characteristics. The fuel compositions were optimized for efficient transmutation of minor actinide. The transmutation of long-lived fission products was also considered.  相似文献   
79.
Spherical Si solar cell, which is made up of Si spheres with a diameter of approximately 1.0 mm, is expected to be a promising candidate for low consumption of Si feedstock and simple process technology. This paper describes the formation process and the structure of a concentrator module in detail. The concentrator lens was formed by casting with ultraviolet light hardening resin. The concentration ratio was 4.4 times and the pitch between the spheres was 2.0 mm. By this module design, it was possible to realize a consumption of the Si feedstock of about 3.0 g/W. Conversion efficiencies of 11.3% from single-sphere cell, 8.5% from a 23-spheres module and 5.2% from a 105-spheres module under AM1.5, 100 mW/cm2 illumination were achieved.  相似文献   
80.
The thermal diffusivity of neptunium dioxide was measured in the temperature range from 473 to 1473 K by using a laser flash method. The thermal diffusivity slightly decreased with increasing temperature in the temperature range investigated. The heat capacity of NpO2 was measured in the temperature range from 334 to 1071 K by using a drop calorimetry method. The heat capacity of NpO2 determined in this study was slightly larger than that of UO2 and about 7% smaller than that of PuO2. The thermal conductivity of NpO2 was determined from the thermal diffusivity, the heat capacity and the bulk density. It was found that the thermal conductivity of NpO2 from 873 to 1473 K lay between those of UO2 and PuO2.  相似文献   
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