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31.
The modifying of the JT-60U magnet system to the superconducting coils is progressing as a satellite facility for ITER by both parties of Japanese government and European commission in the Broader Approach agreement. The magnet system requires current supplies of 25.7 kA for 18 TF coils and of 20 kA for 4 CS modules and 6 EF coils. The magnet system generates an average heat load of 3.2 kW at 4 K to the cryogenic system. The feeder components connected to the power supply provide current supply. The cooling pipes connected to the cryogenic system provide coolant supply. The instrumentation of the JT-60SA magnet system is used for its operation.  相似文献   
32.
We have developed a new nonstoichiometric Gd3+δ(Al,Ga)5−δO12:Ce garnet scintillator for an X-ray CT scanner. For commercially used scintillators, reproducible luminescence properties are of great importance. We have found that the afterglow properties of the garnet change drastically in the vicinity of the stoichiometric compositions. The most suitable properties are obtained at slightly excess (Gd,Ce) compositions from the stoichiometry. In order to investigate the afterglow properties, crystallography arrangements, phase equilibrium relationship between crystal phases, and luminescence characteristics of host material doped with different valence ions have been examined. The luminescence properties are explained by isoelectronic traps based on the difference in the electronegativity of the dopant and host ions, which would act as electron trap centers and hole trap centers within the band gap.  相似文献   
33.
An overview is given of clinical engineering (CE) activities in Europe, North and South America, and the Far East. The discussion covers what CE is, its economics, in-house service centers, certification, life-support devices, support services for CE, European Community CE activities and directives, and CE trends. Medical equipment and technology management, human factors and quality assurance, increased regulations, new technologies and training, and computerization are also addressed  相似文献   
34.
Transcutaneous Blood Flow Measurement by Electromagnetic Induction   总被引:1,自引:0,他引:1  
A new induction flowmeter which can measure the blood flow from the skin surface is discussed theoretically and experimentally. A pair of electrodes placed on the skin detect the EMF induced by the interaction of the blood flow and a magnetic field applied from outside the skin. The relation between the EMF and the flow rate, which is obtained theoretically, is also confirmed experimentally within the error of 10 percent.  相似文献   
35.
This study defines normative flow velocity (FV) ranges for the common carotid (CCA), internal carotid (ICA) and middle cerebral arteries (MCA), compares them to subjects with nonfocal vascular disease (mild to moderate hypertension, diabetes, hyperlipidemia or coronary artery disease), and clarifies the association between carotid and MCA FVs. FVs were measured by carotid and transcranial Doppler ultrasonography in 278 healthy and 190 vascular-disease subjects. Normative FV ranges for CCA, ICA and MCA were large in healthy subjects, with modest gender and age differences. Vascular-disease subjects had similar FVs to healthy controls. MCA FVs were significantly correlated with carotid FVs (r ranged 0.26-0.50), but were only weakly or not significantly associated with them (beta ranged 0.08-0.18) when controlling for age and gender. These findings suggest that normative FVs are not affected by the presence of nonfocal vascular disease, but carotid FVs do not aid in assessing MCA FVs.  相似文献   
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37.
Computational algorithms being developed and used in scientific research processes have gone on increasing by rapid advance of computer technology and computational techniques. These algorithms have generally been distributed and it has not always been easy for general users to find the most suitable ones for their specific problem solving.

In this paper, an approach toward integrated algorithm information system is presented. The system is intended to store the algorithm information to be used in a wide range of scientific fields, and to provide the information corresponding to requests of general users with various motivations. The algorithm information is represented in a conceptual framework consisting of three sets of attributes which are selected to describe essential features of the algorithm. The experimental system shows that the information retrieval method is effective not only for the dissemination of the algorithm information but also for its organization and maintenance. However, it is pointed out and discussed that some techniques in artificial intelligence researches should be required for more selective and critical searches using implicit information among algorithms.  相似文献   

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39.
Methacrylic acid (MAA) and methyl methacrylate (MMA) were grafted onto nylon 6, cellulose triacetate, cotton, viscose rayon, and polyester fibers, and the stereoregularities of the grafted polymers were determined. The graft polymerization was carried out with preirradiation techniques using γ-rays from a Co 60 source. The grafted copolymers were then separated from the homopolymers by Soxhlet extraction. The grafted (branch) polymers were isolated from the trunk polymers by acid hydrolysis and their stereoregularity was determined with a 100 MHz NMR spectrometer. The stereo-regularity of PMAA or PMMA grafted onto viscose rayon or cotton fiber was different from that of the polymers formed in ordinary radical polymerization.  相似文献   
40.
Human placenta gangliosides   总被引:2,自引:0,他引:2  
Gangliosides extracted from human placenta were composed of four major components (G1–G4), which were purified by silica beads column chromatography. The structures of these gangliosides were analyzed by exoglycosidase treatments, 400 MHz proton magnetic resonance spectroscopy and gas chromatography-mass spectrometry and were concluded to be as follows: Gangliosides containing more than 10 sugar residues were observed in addition to the above four major components. But ganglio-series gngliosides were undetectable in the placenta.  相似文献   
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