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41.
Inoue Y Nomura Y Nakaoka T Watanabe M Kiryu S Okubo T Ohtomo K 《Magnetic resonance imaging》2005,23(5):641-645
The aim of this study was to investigate the effect of temporal resolution on the estimation of left ventricular (LV) function by cardiac magnetic resonance (MR) imaging using a steady-state free precession (SSFP) sequence. Left ventricular function was assessed by cine MR imaging using a segmented SSFP sequence in 10 healthy volunteers. Views per segment (VPS) were set at 8 and 20, resulting in high and low true temporal resolution, respectively. Irrespective of VPS, images were reconstructed at 40 cardiac phases, providing high apparent temporal resolution. Data were analyzed using 40, 20 and 10 phases to simulate different apparent temporal resolutions. Increasing the cardiac phases used for analysis slightly decreased mean end-systolic volume (ESV) and slightly increased mean ejection fraction (EF). No substantial difference in estimates of end-diastolic volume (EDV) was found between VPSs of 8 and 20. Imaging with a VPS of 20 yielded a larger ESV and smaller EF than imaging with a VPS of 8 when 40 phases were used. In conclusion, low true temporal resolution causes overestimation of ESV and underestimation of EF. Improvement of apparent temporal resolution mildly reduces but does not eliminate the errors caused by low true temporal resolution. 相似文献
42.
We have investigated the pressure-induced Raman spectral changes of 1-ethyl-3-methylimidazolium tetrafluoroborate ([emim][BF4]). We found that [emim][BF4] did not crystallize up to 1.2 GPa. The Raman CH stretching spectra arising from the CH3 groups of the ethyl-chain and the CH3 group adjacent to the imidazolium-ring in [emim]+ cation largely changed against pressure. Moreover, the Raman intensity of the CH2 (N) bending band arising from the alkyl-chain drastically changes with increasing pressure, but that of the imidazolium-ring in-plane bending band arising from the imidazolium-ring is independent of pressure. Our results show that the environment around the alkyl-chain of [emim][BF4] is largely perturbed rather than that around the imidazolium-ring upon compression. 相似文献
43.
Conventional stochastic resonance in terms of signal-to-noise ratio refers to the amplification of a weak signal in the average of the output. In this framework, only the first moment of the output is used for extracting the information about the input signal. However, higher order moments are also modulated by the input signal. We report the occurrence of stochastic resonance in higher moments. Furthermore, by the linear combination of moments, the signal-to-noise ratio improves compared with the conventional method, which uses the lowest moment only. 相似文献
44.
Hideki Funamizu Tsuyoshi KatoYoshihisa Aizu Yukihiro Ishii 《Optics Communications》2012,285(24):4987-4992
We present the correction of a quadratic phase error in two-wavelength digital holographic interferometry using laser diodes. This phase error arises from numerical reconstructions of wavefronts from digital holograms based on the Fresnel diffraction integral. To correct the quadratic phase error, it is numerically produced by computer on the basis of the theoretical prediction and is subtracted from the phase difference map in two-wavelength digital holographic interferometry. Experimental results show that the method of correction in this paper is useful for two-wavelength digital holographic interferometry using laser diodes. 相似文献
45.
Ryota Tsutsumi Tokio Sasaki Chisato Hashiguchi Ryota Yamazaki Syuji Fujii 《Composite Interfaces》2018,25(8):743-760
In order to reinforce the composite consisting of isoprene rubber (IR) and calcium carbonate (CaCO3) particles, the surface treatment of CaCO3 particles with a mixture of amino- and mercapto-functional silane coupling agents was investigated. The quantity of chemisorbed silanes in treated CaCO3 measured using thermogravimetry was greater for amino- than for mercapto-silane and for the tri- than for the dialkoxy structure. Second, the molecular mobility of polycondensate of the mixtures with the trialkoxy structure measured using 1H pulse nuclear magnetic resonance had the least molecular mobility, i.e., formed the highest density network. The greater values of stress at 500% strain, fracture stress, and elongation at break were determined for the treatment with amino- and mercapto-functional silanes having a trialkoxy structure from the stress-strain curves of composite. The mixture treatment with dialkoxy structure and with amino- or mercapto-functional silane only did not improve the mechanical properties sufficiently. Interactions between the amino group and the CaCO3 surface, covalent bonding between the mercapto group and the IR, and high density network formation of trialkoxy silane were important for improving the mechanical properties of the composite. 相似文献
46.
Hoon Kim Toshihiko Koseki Tomohiro Ohta Hiroshi Sato Yukihiro Shimogaki 《Applied Surface Science》2006,252(11):3938-3942
The adhesion of Cu on Ru substrates with different crystal orientations was evaluated. The crystal orientation of sputter deposited Ru could be changed from (1 0 0) to (0 0 1) by annealing at 650 °C for 20 min. The adhesion of Cu was evaluated by the degree of Cu agglomeration on Ru. Cu films on annealed Ru films with the (0 0 1) crystal orientation showed 28% lower RMS values and 50% lower Ru surface coverage than Cu as-deposited on Ru having the (1 0 0) crystal orientation after annealing at 550 °C for 30 min, which suggest that Cu wettability on the Ru(0 0 1) was better than that on the Ru(1 0 0) plane. The low lattice misfit of 4% between Cu(1 1 1) and Ru(0 0 1) may be the reason for this good adhesion property. 相似文献
47.
H. Kira Y. Sakaguchi T. Oku J. Suzuki M. Nakamura M. Arai K. Kakurai Y. Endo Y. Arimoto T. Ino H.M. Shimizu T. Kamiyama K. Tsutsumi K. Ohoyama H. Hiraka K. Yamada L.-J. Chang 《Physica B: Condensed Matter》2011,406(12):2433-2435
We have begun the development of an in-situ spin-exchange optical pumping (SEOP) system aiming to use it as a neutron spin filter for incident beam polarization at the Japan Proton Accelerator Research Complex (J-PARC). To use it, it is recommended that the optics be adjusted easily, have high stability, and have a small size. In this paper we improved our previous SEOP system aiming to use it in J-PARC and performed a neutron beam test at the JRR-3 NOP beamline to see the performance of the neutron spin filter (NSF). The polarization of the 3He gas reached 73%. This paper gives the present status of the development of in-situ SEOP system in J-PARC. 相似文献
48.
Ohne Zusammenfassung 相似文献
49.
Ohne Zusammenfassung 相似文献
50.
Visible (VIS) and short-wave near infrared (SW-NIR) spectroscopy was used for non-destructive analysis of ivories. VIS-SW-NIR (500-1000 nm) spectra were measured in situ for five kinds of ivories, that is two subspecies of African elephants, mammoth, hippopotamus, and sperm whale. Chemometrics analyses were carried out for the spectral data from 500 to 1000 nm region. The five kinds of ivories were clearly discriminated from each other on the scores plot of two principal components (PCs) obtained by principal component analysis (PCA). It was noteworthy that the ivories of the two subspecies of African elephants were discriminated by the scores of PC 1. The loadings plot for PC 1 showed that the discrimination relies on the intensity changes in bands due to collagenous proteins and water interacting with proteins. It was found that the scores plot of PC 2 is useful to distinguish between the ivories of the two subspecies of African elephants and the other ivories. We also developed a calibration model that predicted the specific gravity of five kinds of ivories from their VIS-SW-NIR spectral data using partial least squares (PLS)-1 regression. The correlation coefficient and root mean square error of cross validation (RMSECV) of this model were 0.960 and 0.037, respectively. 相似文献