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1.
To prevent loss of w3 polyunsaturated fatty acids over long-term preservation, the effects of temperature and oxygen absorber on the fatty acids of sardine oil stored in air-tight film were studied. The fatty acids of sardine oil and lipids in the diet of experimental animals rapidly decreased over 1 month at 22°C. The amounts in the diet decreased slowly at 2°C; however, no alterations in the oil samples were observed for 6 months. Also, the amounts did not change at -30°C. Significant changes in samples treated with oxygen absorber were not observed under all temperatures during 6 months storage (P > 0.05). These results indicate that treatment with an oxygen absorber and/or freezing can prevent ω3 polyunsaturated fatty acids of fish oil from decreasing during storage.  相似文献   
2.
Ceramic and piezoelectric properties of the Pb(Co1/3Nb2/3)O3-PbTiO3-PbZrO3 system were investigated. The system contains rhombohedral, tetragonal, and pseudocubic phases at room temperature. The triple point is at 0.07Pb(Co1/3Nb2/3)O3-0.43PbTiO3-0.50PbZrO3. High dielectric constants (750 to 1500) and radial coupling coefficients (40 to 45%) and low average temperature coefficients of resonant frequency (of the order of 10-6°C) were obtained for compositions near the morphotropic phase boundary.  相似文献   
3.
This paper applies ISM (interpretive structural modelling) to analyse preference structure in a multiobjective problem of a dynamic environmental-economic model, and terms this method IPSM (interpretive preference structural modelling). Multi-objectives in the model include minimizing social cost of pollution, and maximizing total consumption in a planning interval. IPSM analyses decision-maker's preference relations (mental model) among many Pareto-optimal solutions of the multiobjective systems under the interactive cooperation between the decision-maker and the model-builder, and extracts the decision-maker's preference structure as a hierarchical directed graph, where the vertices of the graph correspond to the Pareto-optimal solutions and the directed edges correspond to the preference relations. An interesting economic interpretation for a preferred solution is discussed in terms of the economic interpretation of the discrete minimum principle.  相似文献   
4.
The dielectric ceramic materiala Ba(Zn1/3Ta2/3)O3–BaZrO3 has extremely low dielectric loss at microwave frequencies. To investigate the lattice vibrations of Ba(Zn,Ta)O3 and Ba(Zr, Zn, Ta)O3 solid solutions, far infrared reflection spectra were measured from 50 to 4000 cm−1 using a Fourier transform infrared spectrometer. These data were analyzed according to the classical dispersion theory. The spectra of Ba(Zn,Ta)O3 are well fitted by using the 14 resonant modes, and the spectra of Ba(Zr, Zn, Ta)O3 solid solution are fitted by assuming the normal distribution on resonant frequencies. The damping constant of these materials is discussed, and the values of tan δ calculated from the dispersion parameters agree with the measured values.  相似文献   
5.
日本では,21世紀半ばに人工の固体物質の代表である解体コンクリート塊の排出量がピークを迎えると同時に,最終処分が困難になる状況が想定されていることから,コンクリート材料の完全資源型の利活用要求はより一層高まるといえる.本研究は,副産微粉,再生骨材などの二次副産材を積極的に混和し,同一産地*種類型の調合条件のもとで,コンクリートの物性改善,資源有効利活用を目的としたコンクリートを製造し,その基礎的物性の評価と環境影響評価を行い,環境保全に資するコンクリート材料の発展的利用のあり方を検討した.  相似文献   
6.
Acid urease derived from Lactobacillus fermentum was applied to reduce ethyl cthe target level (90 μg/L). However, complete prearbamate (EC) formation in California sherry production. Commercial sherry and sherry base were treated with urease under different conditions. Amounts of urea were determined and EC amounts were monitored by gas chromatography. Urea removal by acid urease reduced EC formation during the baking process and effectively maintained EC concentrations below vention of EC was not achieved because of precursors other than urea.  相似文献   
7.
Glasses in the system Al2O3-Y2O3-SiO2, containing TiO2 and La2O3, were investigated. Glasses of high refractive index and elastic modulus were developed. The observed Young's and shear moduli of these glasses show good agreement with theoretical values. Agreement was also found between the observed and calculated values of refractive index when the Appen's empirical coefficients were used.  相似文献   
8.
We develop a self-tuning-type adaptive control for robotic manipulators with six joints, and analyse the stability of the control system. In order to reduce the computational effort for obtaining the control input in real time, a decentralized adaptive control system is designed in which each joint of the manipulator is regarded as a subsystem and controlled independently in parallel. In this control system we regard the interaction among the multiple joints as an unknown input in each subsystem. The influence of the interaction on the stability of the overall control system is analysed using a Lyapunov function. The theoretical result obtained is that the control system is always stable in the sense that the error between the output of the adaptive predictor and the real output (angular velocity of each joint) will not exceed the amount of interaction. This result is verified by some simulation studies.  相似文献   
9.
Abstract

This paper deals with the prediction and management of regional and environmental noise using remote sensing techniques. Landsat-MSS and -TM data are used to estimate noise pollution by means of a group method of data handling. They estimate ground roughness from the proportion of the area occupied by buildings thus determining the shielding factor of noise propagation on the ground. The noise level predicted by the method presented in this paper showed a satisfactory agreement with that obtained from measurements from various other cases in urban areas.  相似文献   
10.
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