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排序方式: 共有1099条查询结果,搜索用时 15 毫秒
101.
Kan Okubo Masakazu Takayama Nobunao Takeuchi 《Electromagnetic Compatibility, IEEE Transactions on》2007,49(1):163-169
To clarify the relationship between earthquakes and electrical phenomena, signals of three parameters were observed continuously at Sennan in Akita Prefecture, Japan: ground acceleration (GAC), earth potential difference (EPD), and electrostatic field in the atmosphere (EFA). A large metal plate was used as an electrostatic antenna to observe EFA variation. For this paper, we used the digital natural observation (D-NOB) method as a signal processing technique and found clear EPD and EFA waveforms during seismic wave propagation. Our observation and examination results show that GAC causes EPD variation. Subsequently, the EPD variation induces EFA variation 相似文献
102.
Perpendicular magnetic recording using a main-pole-driven perpendicular head was tested using electroless-plated flexible disks. Soft magnetic NiFeP films, also produced by electroless plating, were used as an underlayer of a perpendicular recording medium in this test. Two types of flexible double-layer media, composed of an electrodeless-plated CoNiReP film with two types of NiFeP underlayers with a coercivity of 2 and 5.5 Oe, were fabricated, and their recording characteristics were measured. A recording density value of 75 kFRPI was obtained for the medium with the softer magnetic 2-Oe underlayer, about twice as high a value as that for the medium with the 5.5-Oe underlayer 相似文献
103.
104.
Several samples of rare-earth oxides of perovskite structure were developed and investigated between 1.5 and 10 K. The measurements have shown, that these materials have large magnetic moments and most of them exhibit a magnetic phase transition below 4 K. The heat capacities of the samples have been measured with the adiabatic heat-pulse method. The dependence of the heat capacity on the preparation temperature of the samples has been studied. The results of the measurements are presented in this paper. The possibility of using these materials as regenerator materials in cryocoolers, e.g. pulse-tube refrigerators, is discussed. 相似文献
105.
Y Murakami Y Ishinaga K Sano R Murakami Y Kinoshita J Kitamura K Kobayashi S Okada K Matsubara T Shimada S Morioka 《Canadian Metallurgical Quarterly》1996,19(6):473-476
BACKGROUND: Platelet activation and coagulation abnormality have been observed during coronary spasm. It is crucial whether platelet activation occurs even during a nonischemic period. HYPOTHESIS: This study was designed to determine whether platelets might be activated across the coronary bed during a nonischemic interval in patients with vasospastic angina. METHODS: Plasma levels of serotonin, 6-keto-prostaglandin F1 alpha, and catecholamines in the aorta and the coronary sinus were simultaneously measured in 16 patients with vasospastic angina and 13 control patients with nonischemic heart disease. RESULTS: None of these patients showed myocardial ischemia during sampling. The difference in transcardiac plasma levels of serotonin in patients with vasospastic angina was significantly higher than that in controls (1.48 +/- 1.08 ng/ml vs. 0.07 +/- 0.12 ng/ml, respectively, p < 0.001). Coronary sinus plasma norepinephrine levels in these two groups were almost the same (204.8 +/- 110.8 pg/ml vs. 190.4 +/- 131.6 pg/ml, respectively). The ratio of 6-keto-prostaglandin F1 alpha in the coronary sinus and the aorta was not different between the two groups (1.17 +/- 0.96 in patients with vasospastic angina vs. 1.15 +/- 0.68 in controls). CONCLUSIONS: These data suggest that platelet activation across the coronary bed should be ascribed to endothelial dysfunction. Lack of compensatory enhancement of prostacyclin production might be concerned with dysfunction of coronary endothelial cells in these patients. 相似文献
106.
107.
AS Landsend M Amiry-Moghaddam A Matsubara L Bergersen S Usami RJ Wenthold OP Ottersen 《Canadian Metallurgical Quarterly》1997,17(2):834-842
The delta 2 glutamate receptors are prominently expressed in Purkinje cells and are thought to play a key role in the induction of cerebellar long-term depression. The synaptic and subsynaptic localization of delta receptors in rat cerebellar cortex was investigated with sensitive and high-resolution immunogold procedures. After postembedding incubation with an antibody raised to a C-terminal peptide of delta 2, high gold particle densities occurred in all parallel fiber synapses with Purkinje cell dendritic spines, whereas other synapses were consistently devoid of labeling. Among the types of immunonegative synapse were climbing fiber synapses with spines and parallel fiber synapses with dendritic stems of interneurons. At the parallel fiber-spine synapse, gold particles signaling delta receptors were restricted to the postsynaptic specialization. By the use of double labeling with two different gold particle sizes, it was shown that delta and AMPA GluR2/3 receptors were colocalized along the entire extent of the postsynaptic specialization without forming separate domains. The distribution of gold particles representing delta receptors was consistent with a cytoplasmic localization of the C terminus and an absence of a significant presynaptic pool of receptor molecules. The present data suggest that the delta 2 receptors are targeted selectively to a subset of Purkinje cell spines and that they are coexpressed with ionotropic receptors in the postsynaptic specialization. This arrangement could allow for a direct interaction between the two classes of receptor. 相似文献
108.
N Hori Y Endo K Okubo K Murakawa M Yokoyama R Matoba K Matsubara 《Canadian Metallurgical Quarterly》1997,4(5):315-319
The list of LDL receptor superfamily relatives is still growing. The two most recently discovered family branches are (1) a set of receptors characterized by expression in brain and a very close relationship to the LDL and VLDL receptors, and (2) highly cross-species (man, mouse, rabbit, chicken) conserved complex mosaic receptors which contain structural domains so far not found in the superfamily. At present, we know very little about the physiological function(s) of these molecules. They can be safely assumed, based on the presence of seven, eight or 11 clustered LDL receptor ligand binding repeats, to recognize mammalian apolipoprotein E but, based on the absence of apolipoprotein E in birds, they may exhibit interactions quite different from and/or in addition to typical lipoprotein receptors in vivo. 相似文献
109.
Annealing effects of a high-quality ZnTe substrate 总被引:1,自引:0,他引:1
Kenji Yoshino Minoru Yoneta Kenzo Ohmori Hiroshi Saito Masakazu Ohishi Takayuki Yabe 《Journal of Electronic Materials》2004,33(6):579-582
The sharp photoluminescence (PL) and optical-reflection spectra in the bandedge region of the high-quality nondoped ZnTe substrate
(100) were observed at 4.2 K. Free exciton, associated with lower and upper polaritons (EXL and EXU) at 2.382 eV and 2.381 eV, respectively, were clearly observed. This meant that this substrate was high quality. The intensity
of a bound exciton peak (2.375 eV), which is caused by a Zn vacancy, of a neutral acceptor decreased with an increase of the
Zn vapor pressures. 相似文献
110.