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61.
The feasibility of a proposed system that combines a magnesium oxide/water chemical heat pump and a diesel engine as a cogeneration system is discussed based on experimental results. The combined system is intended to utilize the waste heat discharge from the engine by means of the chemical heat pump and to level the heat supply load of the engine, allowing enhanced energy utilization. The thermal performance of the chemical heat pump in the cogeneration system is estimated based on the results of a packed‐bed experiment. The estimation indicates that by storing the waste heat from the engine during low demand periods, the cogeneration system can produce more than several times the standard thermal output of the diesel engine during peak demand periods. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
62.
The thermal performance of a chemical heat pump that uses the reaction system of calcium oxide/lead oxide/carbon dioxide, which is developed for utilization of high‐temperature heat above 800°C, is studied experimentally. The thermal performance of a packed‐bed reactor of a calcium oxide/carbon dioxide reaction system, which stores and transforms a high‐temperature heat source in the heat pump operation, is examined under various heat pump operation conditions. The energy analysis based on the experiment shows that it is possible to utilize high‐temperature heat with this heat pump. This heat pump can store heat above 850°C and then transform it into a heat above 900°C under an approximate atmospheric pressure. An applied system that combines the heat pump and a high‐temperature process is proposed for high‐efficiency heat utilization. The scale of the heat pump in the combined system is estimated from the experimental results. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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The first sea trial of submarine optical fiber cable using dispersion-shifted fibers is described. The discussion covers the fiber structural design, cable manufacturing results, fiber splicing, cable laying results, and a high-accuracy measurement technique for optical loss and chromatic dispersion. The results demonstrate the feasibility of long-span, high-capacity 1.5-μm submarine optical fiber cable 相似文献
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Hirokazu Yoshizawa Gabor C. Temes 《Analog Integrated Circuits and Signal Processing》2006,48(3):267-270
This paper describes a high-precision switched-capacitor (SC) track-and-hold amplifier (THA) stage. It uses a novel continuous-time
correlated double sampling (CDS) scheme to desensitize the operation to amplifier imperfections. Unlike earlier predictive-CDS
THAs, the circuit does not need a sample-and-held input signal for its operation. During the tracking period, an auxiliary
continuous-time signal path is established, which predicts the output voltage during the holding period. This allows accurate
operation even for low amplifier gains and large offsets over a wide input frequency range. Extensive simulations were performed
to compare the performance of the proposed THA with earlier circuits utilizing CDS. The results verify that its operation
is far more robust than that of any previously described THA. 相似文献
68.
Kanako Kaji Iwao Yoshizawa Choji Kohara Kuniaki Komal Motoyoshi Hatada 《应用聚合物科学杂志》1994,51(5):841-853
Flame-retardant polyethylene foam was successfully obtained by grafting a vinyl phosphonate oligomer onto polyethylene foam of an open-cell type using a simultaneous radiation grafting technique. The foam was impregnated with the oligomer and irradiated in a nitrogen atmosphere with an electron beam. The grafted foam thus obtained was found to pass the three most severe flammability tests that have to be cleared when the foam is to be used for materials where high flame-retardant property is required. No hydrogen cyanide was detected in burning exhaust gas of the grafted foam. © 1994 John Wiley & Sons, Inc. 相似文献
69.
K Ichikawa M Baba I Yoshizawa Y Kawano T Noma 《Canadian Metallurgical Quarterly》1995,44(9):1132-1139
To analyse the change of the immunological response in the remission state of children with bronchial asthma, we studied the interleukin 1 (IL-1) production of peripheral blood mononuclear cells (PBMC) obtained from children with bronchial asthma sensitized by mite antigen. After PBMC were cultured for 24 hours with Dermatophagoides farinae (Df) or lipopolysaccharide (LPS), the PBMC-derived culture supernatant was estimated for IL-1 alpha and beta by enzyme-linked immunosorbent assay (ELISA). PBMC from some of subjects with active asthma produced IL-1 alpha and beta without any stimulation, but not those from controls or subjects in remission. IL-1 alpha and beta production of PBMC stimulated with Df was observed in all three groups, but IL-1 produced by subjects with active asthma was higher than that produced by subjects in the other two groups. Moreover, when PBMC were incubated with LPS, the secretion of both IL-1 alpha and beta was enhanced. PBMC from patients with active asthma produced both IL-1 alpha and beta in amounts comparable to those produced by PBMC from control subjects, but IL-1 production of PBMC from patients in remission was lower than in the other two groups. IL-1 beta production was about ten times as much as IL-1 alpha. Df-induced IL-1 production of PBMC from asthmatic patients sensitized by mite antigen, which was increased in the active state, was down-regulated in the remission state. Moreover, nonspecific stimuli such as LPS may induce the suppressive factors which down-regulate IL-1 production.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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