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61.
62.
When using high pressure differential thermal analysis to study the stability of a fatty methyl ester or triglyceride in an atmosphere of air, a departure from the base line in the exothermic curve is observed. The point where an extension line from the base line intersects a tangent line to the departure curve was selected as the transition point in the exothermic curve. For each sample studied, temperature at this transition point showed good reproducibility. The influence of sample container and air pressure upon the temperature of the transition point in the exothermic curve (TTE) was examined. A linear correlation between the number of double bonds in the sample and TTE was observed.  相似文献   
63.
A rare case of synovial osteochondromatosis of the temporo-mandibular joint is presented. Important diagnostic information can be obtained by CT, MRI, 99m Tc bone scan and aspiration biopsy. Observation using a light microscope showed mild cellular atypia, but the hallmarks characteristic of chondrosarcoma were not found. Observation using an electron microscope showed the mature chondrocytes contained a well-developed rough endoplasmic reticulum. Histological evaluation indicated that the present case was benign synovial osteochondromatosis in an early stage.  相似文献   
64.
Commercially available preparations of CLA are composed of almost equal amounts of 9-cis,11-trans (9c,11t)-CLA and 10-trans,12-cis (10t,12c)-CLA. Each isomer was fractionated and enriched, for availability as a food supplement, by a process comprising selective esterification with l-menthol by Candida rugosa lipase, distillation, and n-hexane extraction. The first selective esterification of CLA isomers was conducted with an equimolar amount of l-menthol of 30°C. The oil phase of the reaction mixture was fractionated into an l-menthyl ester fraction (9c,11t-CLA rich) and an FFA fraction (10t,12c-CLA rich) by distillation. The FFA fraction was esterified again with an equimolar amount of l-menthol to enrich 10t,12c-CLA. The 10t,12c-CLA preparation was obtained as the resulting FFA fraction by distillation. 10t,12c-CLA was enriched to 91% with 40% recovery. To enrich 9c,11t-CLA, the l-menthyl ester fraction in the first esterification was chemically hydrolyzed, and the resulting FFA were esterified again with an equimolar amount of l-menthol. The 9c, 11t-CLA preparation was obtained by chemical hydrolysis of the resulting l-methyl ester fraction, followed by n-hexane extraction. 9c,11t-CLA was enriched to 94% with 42% recovery. This effective process for purification of CLA isomers using l-methol is applicable to the production of food supplements.  相似文献   
65.
This paper reports a study on the possibility of an aerial flashover between a coil conductor and a casing in rotating machines under the application of a lower voltage than Paschen's voltage, even when enough insulation distance is secured. The time lag to aerial flashover originating from surface flashover was measured. To understand the aerial flashover influenced by the parameters of the voltage application circuit, the aerial flashover distance was measured using a cable which had a simulated pore to confirm the above issue. The surface flashover characteristic was also measured using a photomultiplier tube (PMT). It became clear that aerial flashover occurred a few milliseconds after surface flashover generation. After showing the peak, the aerial flashover distance decreased with increasing time constant. The surface flashover time estimated by the PMT output exhibited different values with change of capacitance when the time constant is larger. On the other hand, the average surface flashover current was almost the same in spite of the change of capacitance. From these results, it was concluded that the aerial flashover distance was influenced by the time constant of the circuit. © 2012 Wiley Periodicals, Inc. Electr Eng Jpn, 180(3): 9–17, 2012; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21295  相似文献   
66.
Video Scene Annotation Based on Web Social Activities   总被引:1,自引:0,他引:1  
This article describes a mechanism to acquire the semantics of video content from the activities of Web communities that use a bulletin-board system and weblog tools to discuss video scenes.  相似文献   
67.
An adaptive learning control scheme intended to the on-line optimization of sculptured surface cutting process is presented. The scheme uses a back-propagation neural network to learn the relationships between process inputs and process states. The cutting parameters of the process model are optimized through a genetic algorithms(GA). The capacity of the proposed scheme for determining optimum process inputs under a variety of process conditions and optimization strategies is evaluated on the basis of milling of a sculptured surface using a ball-end mill. The experimental results show that the neural network could model the cutting process efficiently, and the cutting conditions such as spindle speed could be regulated for achieving high efficiency and high quality. Therefore the proposed approach can be well applied to the manufacturing of dies and molds.  相似文献   
68.
Homogeneous columnar Cu film with fully embedded nanotwins was successfully fabricated on Ti/Cu seed layer on silicon wafer. The nanotwins with thickness of tens of nanometers are generally parallel to the silicon surface, showing a strong (111) preferred orientation. The acid concentration was found to be important in influencing the formation of nanoscale twins. By adjusting the acid concentration, the nanotwins can be induced from the top columnar grain to middle columnar grain and reach the bottom equiaxed grain, and a microstructural transformation model was given. A theory focusing on the cathode overpotential was proposed to reveal the effect of acid concentration on the growth mechanism of nanoscale twins. An appropriate adsorption proportion of hydrogen on cathode (acid concentration 17 ml L?1) could increase the overpotential which supplies adequate nucleation energy for nanoscale twins formation.  相似文献   
69.
Boolean network tomography is a promising technique to achieve fault management in networks where the existing IP-based troubleshooting mechanism cannot be used. Aiming to apply Boolean network tomography to fault management, a variety of heuristic methods for configuring monitoring trails and paths have been proposed to localize link failures in managed networks. However, these existing heuristic methods must be executed in a centralized server that administers the entire managed network and the methods present scalability problems when applied to large-scale managed networks. Thus, this paper proposes a novel scheme for achieving lightweight Boolean network tomography in a decentralized manner. The proposed scheme partitions the managed network into multiple management areas and localizes link failures independently within each area. This paper also proposes a heuristic network partition method with the aim of efficiently implementing the proposed scheme. The effectiveness of the proposed scheme is verified using typical fault management scenarios where all single-link failures and all dual-link failures are localized by the least number of monitoring paths on predetermined routes. Simulation results show that the proposed scheme can greatly reduce the computational load on the fault management server when Boolean network tomography is deployed in large-scale managed networks. Furthermore, the degradation of optimality in the proposed scheme can be mitigated in comparison with a centralized scheme that utilizes heuristics to reduce the computational load on the centralized server.  相似文献   
70.
Diacylglycerol (DAG) is a component of various vegetable oils. Approximately 70% of the DAG in edible oils are in the configuration of 1,3-DAG. We recently showed that long-term ingestion of dietary oil containing mainly 1,3-DAG reduces body fat accumulation in humans as compared to triacylglycerol (TAG) oil with a similar fatty acid composition. As the first step to elucidate the mechanism for this result, we examined the difference in the bioavailabilities of both oils by measuring food energy values and digestibilities in rats. Energy values of the DAG oil and the TAG oil, measured by bomb calorimeter, were 38.9 and 39.6 kJ/g, respectively. Apparent digestibility expressed according to the formula: (absorbed) x (ingested)−1x100=(ingested—excreted in feces)x(ingested)−1x100 for the DAG oil and the TAG oil were 96.3±0.4 and 96.3±0.3% (mean±SEM), respectively. The similarity in the bioavailabilities of both oils supports the hypothesis that the reduced fat accumulation by dietary DAG is caused by the different metabolic fates after the absorption into the gastrointestinal epithelial cells.  相似文献   
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