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91.
Japan's Specifications and Standards for Food Additives, 7th Edition (JSFA-VII) does not set limits for total contents of water-soluble chlorides and water-soluble sulfates (water-soluble inorganic salts) in food color aluminum lakes (FC-Als). However, the regulatory limit is 2% in JECFA and CFR. We used column switching suppressor-type ion chromatography (CSS-IC) for determination of anions. The total contents of water-soluble inorganic salts in FC-Als (112 qualified samples) were determined using the modified CSS-IC from fiscal year 1998 to fiscal year 2003. Total contents of water-soluble inorganic salts in four samples exceeded 2%. From an international point of view, it is desirable that the total content of water-soluble inorganic salts in FC-Al should again be regulated in Japan.  相似文献   
92.
Waste tyre and plastic such as polyethylene terephthalate can be utilized as a useful material for conversion of solar energy into chemical energy by solar thermochemical gasification into synthesis gas (CO+H2) using concentrated solar energy. In the present paper, the gasification of waste tyre (C: 86 wt.%, H: 8.4 wt.%) and of PET (C10H8O4)n, were studied using ZnO as a donor of oxygen in the infra-red furnace at 1373 K. For the gasification of tyre, most of the chemically bound hydrogen was converted into H2 (62%) and CH4 (29%) gases, while 71 mole% of the inherent carbon was gasified to CO (36%), CH4 (29%), C2H4 (2%), and CO2 (4%) in 200 s of the decomposition reaction. The CO2:CO ratio was about 1/10, indicating that the carbon in the waste tyre can be converted effectively to gaseous fuels. In the experiment without ZnO, the conversion efficiency of C and H were decreased to 17% and 77%, respectively. However an appreciable effect of ZnO on the enhancement of the gasification of PET was not observed.  相似文献   
93.
94.
In this paper, a limit bending moment equation applicable to all types of planar and non-planar flaws in wall-thinned straight pipes under bending was proposed. A system to rationally classify the planar/non-planar flaws in wall-thinned pipes was suggested based on experimental observations focused on the fracture mode. The results demonstrate the importance of distinguishing between axial and circumferential long flaws in wall-thinned pipes.  相似文献   
95.
A general model to treat multiphase diffusion in an impregnated semi-infinite couple, a finite/semi-infinite couple, and a finite/finite couple, under conditions of zero zurface flux, is presented. The model is based both on the numerical solutions previously presented for the multiphase diffusion in semi-infinite and infinite media to which Boltzmann's transformation can be applied and on the finite difference solutions with a variable grid for the multiphase diffusion to which the transformation cannot be applied. Not only critical layer widths for the occurrence of a new phase and the disappearance of a pre-existing phase but also criteria to calculate or not a change in concentration for a terminal phase are introduced in the model in order to diminish the number of iterations, in the calculation. Typical examples to which the model has been applied are discussed.  相似文献   
96.
In this paper, an image processing strain measurement system was extended so that fracture behavior of wall-thinned pipes, such as out of plane and large plastic deformation observed in bulging, can be evaluated by the system. Regular grids with nominal size of 10 mm × 10 mm were marked on 100A carbon steel pipes and the images taken with 6 CCD cameras of 15 million pixels were correlated to achieve resolution of 0.3% strain. Strain of the cylinder's outer surface was evaluated by (1) modeling the grids as a cylindrical shell, (2) measuring deformation of the grid on a projected plane, and (3) applying an updated Lagrangian method. The validity of the system was confirmed by applying the proposed system to the burst tests of a wall-thinned cylinder. In addition, the system measured the non-uniform strain distribution that explained the unexpected cracking location.  相似文献   
97.
We propose and experimentally demonstrate the temporal-Talbot-effect (TTE)-based preprocessing for the pattern-effect reduction in the all-optical clock recovery using a semiconductor-optical-amplifier (SOA)-based fiber ring laser (SOA-FRL). The TTE-based preprocessing successfully reduced the pattern effects of the recovered clock pulses, so that the 10-GHz clear optical clock pulses were recovered from a 10-Gbit/s return-to-zero on–off keying (RZ-OOK) pseudo-random bit sequence (PRBS) optical signal. “Peak variation” and “Pattern-dependent intensity noise (PDIN)” were proposed and were utilized as parameters to quantitatively evaluate the pattern effects, from which recovered clock pulses suffer, in the temporal domain and the frequency domain, respectively. Peak variation was reduced from 77.2% to 36.2%, and PDIN was improved from ?103 dBc/Hz to ?110 dBc/Hz with the aid of the TTE-based preprocessing. Furthermore, we examined the tolerance of the proposed technique by intentionally deviating the input signal’s bit-rate by ±190 Mbit/s (±2% of the bit-rate) from the optimum condition for the TTE. As compared with the PDIN value for the pulse train obtained by the direct injection of the non-processed signal into the SOA-FRL, the PDIN of the recovered clock pulses using the preprocessed signal indicated improvements over the entire measurement range of ±190 Mbit/s, which corresponds to the wavelength-dispersion deviation of ±56 ps/nm (±4% of the wavelength-dispersion applied to the input signal) from the optimum value.  相似文献   
98.
In a new process for reducing adhesion of ice to aluminium alloy used in refrigerators, an application of a special organosiloxane to the anodized surface is followed by heat treatment. Three organohydrosiloxanes and three variations of heat treatment were examined in respect of their effect on resistance to abrasion and corrosion. The treatments were more effective with 2S grade aluminium than with 3S. The abrasion resistance was increased about tenfold and it is considered that this improvement results from chemical bonding between the organohydrosiloxanes and anodized layers.  相似文献   
99.
A general model to treat multiphase diffusion in an impregnated semi-infinite couple, a finite/semi-infinite couple, and a finite/finite couple, under conditions of zero surface flux, is presented. The model is based both on the numerical solutions previously presented for the multiphase diffusion in semi-infinite and infinite media to which Boltzmann’s transformation can be applied and on the finite difference solutions with a variable grid for the multiphase diffusion to which the transformation cannot be applied. Not only critical layer widths for the occurrence of a new phase and the disappearance of a pre-existing phase but also criteria to calculate or not a change in concentration for a terminal phase are introduced in the model in order to diminish the number of iterations in the calculation. Typical examples to which the model has been applied are discussed.  相似文献   
100.
Electric power systems in Japan are composed of remote and distributed location of generators and loads mainly concentrated in large‐demand areas. The structures having long‐distance transmission tend to produce heavy power flow with increasing electric power demand. In addition, some independent power producers (IPP) and power producer and suppliers (PPS) are participating in the power generation business, which makes power system dynamics more complex. However, there was little observation as a whole power system. In this paper the authors present a global monitoring system of power system dynamics by using the synchronized phasor measurement of demand‐side outlets. Phasor Measurement Units (PMU) are synchronized based on the global positioning system (GPS). The purpose of this paper is to show oscillation characteristics and methods for processing original data obtained from PMU after certain power system disturbances triggered by accidents. This analysis resulted in the observation of the lowest and the second lowest frequency mode. The derivation of eigenvalue with the two‐degree‐of‐freedom model brings a monitoring of two oscillation modes. Signal processing based on wavelet analysis and simulation studies to illustrate the obtained phenomena are presented in detail. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 163(3): 10– 18, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20316  相似文献   
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