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51.
Arguing for the need of increasing social awareness on the World Wide Web, we describe a user interface based on the metaphor of windows bridging electronic and physical spaces. We present a system that, with the aim of making online activity perceptible in the physical world, makes it possible tohear people visiting one's website. The system takes advantage of theseamless andcontinuous network connection offered by handheld Web-appliances such as personal digital assistants. 相似文献
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Koichi DoiSatoshi Hino Hiroki MiyaokaTakayuki Ichikawa Yoshitsugu Kojima 《Journal of power sources》2011,196(1):504-507
A lithium silicon alloy was synthesized by mechanical alloying method. Hydrogen storage properties of this Li-Si-H system were studied. During hydrogenation of the lithium silicon alloy, lithium atom was extracted from the alloy and lithium hydride was generated. Equilibrium hydrogen pressures for desorption and absorption reactions were measured in a temperature range from 400 to 500 °C to investigate the thermodynamic characteristics of the system, which can reversibly store 5.4 mass% hydrogen with smaller reaction enthalpy than simple metal Li. Li absorbing alloys, which have been widely studied as a negative electrode material for Li ion rechargeable batteries, can be used as hydrogen storage materials with high hydrogen capacity. 相似文献
56.
Shigehito Isobe Somei OhnukiWilliam I.F. David Matthias GutmannMartin O. Jones Peter P. EdwardsTakayuki Ichikawa Yoshitsugu Kojima 《International Journal of Hydrogen Energy》2011,36(13):7909-7913
We have synthesized a single crystal of lithium amide (LiNH2, LiND2) by melting method, and performed neutron diffraction of the single crystal at variable temperature. LiND2 is tetragonal structure and I-4 space group. Lattice parameters and unit cell volume of LiND2 at room temperature, 50 °C, 100 °C, 150 °C and 200 °C were determined. Both of the lattice parameters and the unit cell volume increase with increase of temperature. From these results, we have estimated coefficient of volumetric thermal expansion αV of LiND2 to be 222 × 10−6/K. With increase of temperature, all thermal ellipsoids gradually expand because of thermal vibration. 相似文献
57.
T. Shimada K. Ichikawa T. Minemura T. Kolodiazhnyi Jonathan Breeze Neil McN. Alford Giuseppe Annino 《Journal of the European Ceramic Society》2010,30(2):331-334
Ba(Mg1/3Ta2/3)O3 ceramic possessing extremely high Q × f value of more than 300 THz at microwave frequency was developed in our previous study. It is of great interest to understand the mechanism of microwave absorption in such a practical material. In the present study we report on the temperature dependence of the dielectric loss in the Ba(Mg1/3Ta2/3)O3. The mechanism of the microwave absorption is discussed using two phonons difference process. The samples were prepared by conventional solid state reaction and sintered at 1893 K in oxygen atmosphere. Dielectric properties in the microwave range were measured by Hakki & Colemann and resonant cavity methods in the temperature range of 20–300 K. Whispering gallery mode technique was used for the measurement of the dielectric properties at the millimeter wave frequency. Dielectric loss of the Ba(Mg1/3Ta2/3)O3 at the microwave frequency increases with temperature between 200 and 300 K in general agreement with the theory of intrinsic dielectric loss derived from the two phonon difference process. However below 200 K, the dielectric loss has shown a distinctive behavior with a loss peak at 40 K. It was inferred that the loss peak of the Ba(Mg1/3Ta2/3)O3 was caused by the local orientation polarization having dispersion at the microwave frequency. 相似文献
58.
K Ishihara H Ichikawa T Takeuchi M Kawamura K Sugita 《Canadian Metallurgical Quarterly》1997,37(6):509-513
We describe a patient who presented with isolated retrograde amnesia of 2-year duration after recovery from viral encephalitis. The patient was a 29-year-old right-handed male dentist and was admitted to our hospital with a complaint of generalized convulsion. Cerebrospinal fluid (CSF) showed mononuclear pleocytosis. Neuroradiological examinations (X-ray CT, MRI and 123I-IMP SPECT) revealed no significant abnormality. Immunological method showed no specific increase of viral antibody titers. However, with a tentative diagnosis of viral encephalitis, administration of acyclovir was started. After 3 weeks he became comprehensive, and several kinds of neuropsychological tests were performed. His intelligence and immediate memory were normal, and his procedural memory of dentist was intact. On the other hand, he could not recall any information about events, both personal and public, occurred within 2 years before the onset of present illness. His autobiographical memory disorder was also demonstrated using a series of weekly comic. In isolated retrograde amnesia following viral encephalitis like this case, memory of relatively short time duration, acquired prior to the onset of present illness, tend to be disturbed. 相似文献
59.
Gene targeting technology has produced mutant mice carrying selective null-mutation of the genes for the components of the renin-angiotensin system. Angiotensinogen null-mutant mice showed not only severe hypotension, but also several abnormal phenotypes in the kidney, including juxtaglomerular (JG) cell hypertrophy, renal arterial hypertrophy, and hypoplastic papilla. Although angiotensin type 1A (AT1A) receptor is by far the most predominant in mice, the phenotypes of AT1A null-deletion mice are much milder than those of angiotensinogen null-mutant mice. Because renin and angiotensin (ANG) production is upregulated in AT1A null-mutant mice, it is conceivable that the AT1B receptor provides compensation for the lost functions of AT1A. The observations in mice with complete absence of a gene product have not elucidated whether the abnormal phenotypes reflect direct effects caused by lack of local tissue action of ANG II or a secondary effect caused by changes in systemic milieu. We have developed chimeric mice that are made up of a mix of clusters of wild-type cells: cells homozygous for AT1A gene deletion. Within a given chimeric mouse, the expressions of renin mRNA and protein are identical between wild-type and mutant cells. In addition, all of the chimeric mice lack the renal arterial lesion observed in standard AT1A null-mutant mice. These findings indicate that both JG cell hypertrophy and renal vascular lesions are caused by systemic, rather than local, mechanism(s). 相似文献
60.
J Taki A Ichikawa K Nakajima M Kawasuji N Tonami 《Canadian Metallurgical Quarterly》1997,24(12):1487-1493
Stress thallium-201 tomography was performed to compare the flow capacities of arterial and saphenous vein grafts in patients with coronary artery bypass grafting (CABG). One hundred and seven consecutive patients (95 male and 12 female; mean age 58+/-9.1 years) underwent exercise-redistribution 201Tl myocardial single-photon emission tomography 4-5 weeks after CABG. When a reversible perfusion defect was present in the area covered by a patent bypass graft, the flow capacity of the graft was defined as insufficient. Of all 285 grafts, 211 were considered as complete bypass. Reversible perfusion defects were present in 29 (27%) of 108 myocardial areas supplied by patent arterial grafts but in only 5 (5%) of 103 myocardial areas supplied by patent saphenous vein grafts (P<0.0001). In the LAD area reversible defects were observed in 22 of 82 areas covered by arterial grafts, in contrast to only 1 of 29 areas covered by venous grafts (P<0.01); in the RCA area reversible defects were observed in 7 of 17 and 4 of 41 areas respectively (P<0.01). There was no difference between the native coronary artery stenosis bypassed by patent arterial and venous grafts (88%+/-12% vs 86%+/-14% respectively, P=0.27). In conclusion, flow capacities during peak myocardial demand were more frequently insufficient in arterial bypass grafts than in saphenous vein grafts. 相似文献