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排序方式: 共有858条查询结果,搜索用时 15 毫秒
51.
Osami Yanagisawa Mitsuru Izumi Wei-Zhi Hu Kenji Nakanishi Hideo Nojima 《Journal of Superconductivity》1999,12(1):307-310
The magnetic behavior of the distorted perovskite manganese, Pr0.65Ca0.35MnO3 was studied by X-band electron spin resonance for powder samples. We observed the onset of the charge-ordered state at T
CO215 K, the antiferromagnetic transition with the peak of the ESR linewidth, H
p–p
at T
AF180 K and the canted antiferromagnetic transition at T
CAF125 K associated with the abrupt increase of both the effective magnetization and H
p–p
. Below 90 K, the absorption intensity profile becomes weakened with decreasing temperature suggesting the existence of some kind of magnetic disorder below 90 K, which is responsible for a part of evidence of the existence of the spin-glass state as has been proposed by Yoshizawa et al., Phys. Rev. B
52, 1689 (1996). 相似文献
52.
Dynamic characteristics of fully depleted ultra-thin film CMOS/SIMOX devices in the range from 50 to 300 K are presented. Discussion is focused on the propagation delay time of CMOS/SIMOX ring oscillators. Using a simple theory, it is shown that the measure propagation delay time is larger than the predicted delay time. Adopting a simple theoretical assumption, it is strongly suggested that the propagation delay time is governed ultimately by the charging and discharging time of the inversion layer in off-to-on and on-to-off processes. The results are corroborated by the fact that fully depleted CMOS/SIMOX operate with extremely small parasitic capacitances 相似文献
53.
The usefulness of INR as an index for assessing anticoagulation was studied using 85 outpatients, all suffering cardiovascular diseases and receiving warfain as subjects. The thrombotest, prothrombin time and INR were measured at follow-up, monthly intervals. The correlation between the thrombotest value and the INR value were assessed retrospectively. We found a stronged correlation between them. The 10 approximately 25% range of the thrombotest value, the therapeutic range, corresponded to 2.29 approximately 3.60 of the INR value. The INR value was more accurate than the thrombotest valve in the situation of prolonged coagulation time. It is recommended to use INR as an objective index for the anticoagulation due to increase accuracy and objectivity when comparing the data among the various institutions. 相似文献
54.
T Masubuchi S Koyama E Sato A Takamizawa K Kubo M Sekiguchi S Nagai T Izumi 《Canadian Metallurgical Quarterly》1998,153(6):1903-1912
Inflammatory cells accumulate within the lungs of cigarette smokers. Current concepts suggest that these cells can induce protease-antiprotease and/or oxidant-antioxidant imbalance(s), which may damage the normal lung alveolar and interstitial structures. Because type II pneumocytes line the alveolar space, and because the inflammatory cells migrate and reside at the alveolus, we postulated that the type II pneumocytes might release chemotactic activity for neutrophils and monocytes in response to smoke extract. To test this hypothesis, A549 cells were cultured and the supernatant fluids were evaluated for the neutrophil and monocyte chemotactic activity (NCA and MCA) by a blind-well chamber technique. A549 cells released NCA and MCA in response to smoke extract in a dose- and time-dependent manner (P < 0.05). Checkerboard analysis showed that the activity was chemotactic. Partial characterization of NCA and MCA revealed that the activity was partly heat labile, trypsin sensitive, and ethyl acetate extractable. Lipoxygenase inhibitors and cycloheximide inhibited the release of NCA and MCA. Molecular sieve column chromatography showed multiple peaks for both NCA and MCA. NCA was inhibited by anti-human-interleukin (IL)-8 antibody, granulocyte colony-stimulating factor (G-CSF) antibody, or leukotriene (LT)B4 receptor antagonist. Monocyte chemoattractant protein (MCP)-1 antibody or LTB4 receptor antagonist inhibited MCA. Immunoreactive IL-8, G-CSF, MCP-1, and LTB4 significantly increased in the supernatant fluids in response to smoke extract. These data suggest that the type II pneumocytes may release NCA and MCA and modulate the inflammatory cell recruitment into the lung. 相似文献
55.
Implications of cultural accommodation–hybridization were explored within the framework of individualism–collectivism. Individualism highlights the personal and centralizes individuals as the unit of analyses, whereas collectivism highlights the social and contextualizes individuals as parts of connected social units. In 2 experiments, the ways in which individualism, collectivism, and identity salience influence social obligation to diverse others was explored. The authors varied the personal goal interrupted (achievement–pleasure), the target (individual–group), and focus (in-group–larger society) of social obligation within subjects. The authors hypothesized that collectivism would increase obligation to the in-group when identity was made salient; that individualism alone would dampen social obligation; and that cultural accommodation–hybridization (being high in both individualism and collectivism) would increase obligation to larger society. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
56.
K Izumi K Kitaura Y Chone H Tate T Nakagawa Y Suzuki K Matsumoto 《Canadian Metallurgical Quarterly》1994,85(6):563-566
Neoplastic lesions of the kidneys in untreated Long-Evans Cinnamon (LEC) rats of 57-118 weeks old (85 males and 34 females) and male F344 rats of 64-93 weeks old (59 males) were examined histologically. The incidences of renal cell tumors in male and female LEC rats were 6/80 (8%) in weeks 57-65, 3/19 (16%) in weeks 66-75, 3/8 (38%) in weeks 76-105 and 7/12 (58%) in weeks 106-118. Of these tumors, 13 were microscopic adenomas and 7 were renal cell carcinomas. The copper content of the kidneys was about three times higher in LEC rats than in F344 rats (P < 0.001), but the iron content of the kidneys was similar in the two strains. 相似文献
57.
The relationship between ductility and material parameters such as grain-boundary (GB) precipitate size and dimple size in an Al-6.0% Zn-2.6% Mg alloy has been studied. Under the condition of a given GB precipitate size, the ductility increases with decreasing number of GB precipitates and dimples per unit area. The critical GB precipitate sizes acting as the nuclei for void formation are deduced. 相似文献
58.
Standardization of transmission system for television satellite broadcasting with multiple sound and/or data signals for an operational broadcasting satellite system is under study in Japan. Based upon result obtained from the BSE experiment, several transmission systems have been developed at the NHK (Japan Broadcasting Corporation). 相似文献
59.
In situ dynamic observations of the deformation and fracture characteristics of alpha/beta brass two-phase bicrystals were made by the solid diffusion method. The results indicated clearly that the crack initiation site was at the interface. The crack propagation direction, in both the alpha and beta phases, was found to be orientation dependent. Complementary experiments on alpha and beta brass single crystals confirmed the theories and results obtained previously on ductile single crystals.On leave from the Mechanical Engineering Department, Al-Azhar University, Cairo, Egypt. 相似文献
60.
A unified scheme for treating generalized superselection sectors is proposed on the basis of the notion of selection criteria to characterize states of relevance to each specific domain in quantum physics, ranging from the relativistic quantum fields in the vacuum situations with unbroken and spontaneously broken internal symmetries, through equilibrium and non-equilibrium states to some basic aspects in measurement processes. This is achieved by the help of c q and q c channels: the former determines the states to be selected and to be parameterized by the order parameters, and the latter provides the physical interpretations of selected states in terms of order parameters. This formulation extends the traditional range of applicability of the Doplicher-Roberts construction method for recovering the field algebra and the gauge group (of the first kind) from the data of group invariant observables to the situations with spontaneous symmetry breakdown: in use of the machinery proposed, the physical and mathematical meaning of basic structural ingredients associated with the spontaneously broken symmetry are re-examined, such as the degenerate vacua parameterized by the variables belonging to the relevant homogeneous space, the Goldstone modes and condensates, etc. The geometrical meaning of the space of order parameters is naturally understood in relation with the adjunction as the classifying space of a sector structure. As further examples of applications, some basic notions arising in the mathematical framework of quantum theory are reformulated and examined in connection with control theory. 相似文献