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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   
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SUMMARY— As morphological changes occurred in the pectoral muscles of chicken carcasses during 48 hr storage at 5°C, two notable phenomena were observed: (1) fragmentation of myofibrils and (2) reversible or irreversible contraction of sarcomeres. When blendorized, myofibrils tend to break into small fragments composed of 1-4 sarcomeres with time post-mortem. It was also found that besides an irreversible post-mortem contraction of sarcomeres generally accepted, a reversible contraction can take place under particular conditions.  相似文献   
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Changes in biochemical properties of myofibrillar proteins of rabbit muscle, which had been subjected to electrical stimulation soon after slaughter, during postmortem storage at 0°C were investigated. Myofibrillar ATPase activity and the ATPase activity of acto-heavy meromyosin (HMM) complex, reconstituted from actin and HMM which had been prepared from at-death and postmortem muscles, decreased at first and then increased slightly during 7 days storage. In addition, the change of the dissociation constant of acto-HMM complex of electrically stimulated muscle during postmortem storage was quite small, i.e., 1.59 ± 10?4M for at-death muscle, 1.70 ± 10?4M for muscle stored for 1 day and 1.49 ± 10?4M for muscle stored for 7 days. This indicates that electrical stimulation treatment minimized the postmortem change of actin-myosin interaction.  相似文献   
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SUMMARY: Studies were made of physicochemical characteristics of natural actomyosin from bovine longissimus of different post-mortem ages and tenderness classifications. Reduced viscosity, ATP sensitivity, and "actin" content (polyethylene sulfonate treatment) were higher for natural actomyosin prepared from muscle 12-24 hr post-mortem than from pre-rigor muscle, which confirms previous reports for rabbit natural actomyosin. A higher actin to myosin ratio in actomyosin from muscle 12-24 hr was therefore postulated. A stronger interaction of actin and myosin in actomyosin from muscle 12-24 hr post-mortem than from pre-rigor or aged muscle was also suggested by reduced viscosity and ultracentrifugation data. Reduced viscosity differences between actomyosins from tough and tender muscle suggested a higher gel character in actomyosin from tough muscle. This possibly indicated a higher content of α-actinin. No consistent differences in ATP sensitivity, myosin and actin content of natural actomyosin of tough and tender muscle were found. Natural actomyosin from muscle aged post-mortem showed the appearance during analytical ultracentrifugation of an additional component which sedimented at about 11S to 12S. This component appeared in the actomyosin prepared from tender muscle after 24 hr but did not appear until 10 days in the actomyosin from tough muscle.  相似文献   
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In this paper, a cooperative control algorithm for multiple step voltage regulator (SVR) using correlation of measurement data of distribution line is proposed. Conventionally, the control time constant of a SVR placed on the feeder end side was set slower than a SVR placed on the substation side. The unnecessary tap movement of SVR was reduced by this setting. In this case, on the condition that “the photovoltaic power generation output of the feeder end fluctuates” and “only SVR of the end side works”, it is a problem that control of SVR becomes slow. By the proposed method, the SVR settled in end side of a feeder can change its tap rapidly only if the SVR settled in sending side of a feeder will not change its tap by using proposed method. The features of the method are followings: (1) to estimate tap change possibility of the sending side SVR using correlation model of both of the SVR, (2) only use local measurement data of the SVRs for tap change control. By the proposed method, unnecessary tap change operation and lag of tap control are reduced without communication networks.  相似文献   
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The antioxidant effects of riboflavin tetrabutylate in emulsions in the dark and under irradiation were studied, as was the effect of racemic (rac) α-tocopherol on the antioxidant action. Riboflavin tetrabutylate had an antioxidant effect in the dark, but an oxidative effect when irradiated, perhaps because the activated oxygen and hydrogen peroxide produced induced lipid peroxidation. The effect of racα-tocopherol on the antioxidant action of riboflavin tetrabutylate was synergistic in the dark. The results showed that riboflavin tetrabutylate was satisfactory as an antioxidant when the emulsion was protected from light and that the effect was increased by the addition of racα-tocopherol.  相似文献   
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