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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Kosuke Morita Kouji Morimoto Daiya Kaji Yu Liang Zhao Atsushi Yoshida Toshimi Suda Akira Yoneda Tetsuya Ohnishi Hiromitsu Haba Eiji Ideguchi Hu Shan Xu Tao Zheng Hisaaki Kudo Keisuke Sueki Kenji Katori Isao Tanihata 《Acta Physica Hungarica A》2004,19(1-2):53-60
A gas-filled type of recoil separator for heavy element research was installed at an experimental hall of RIKEN Linear Accelerator facility to realize getting higher intensity of primary beam and long beam time. Performance of the separator was studied using target recoils and various nuclear reactions. The results show the high performance of the separator for heave element research. As an application of the GARIS, production and identification of an isotope of the 110th element 271[110] have been performed using the 208Pb(64Ni,1n)271[110] reaction. Three decay chains coincide well both in decay times and energies with the ones reported by the group of SHIP experiment at GSI, Germany. Our results provide a confirmation of the synthesis of an isotope 271[110] of element 110. 相似文献
52.
We measured the entire region of mesopic and photopic vision to determine the color zone covering the visual field with unique red, yellow, green, and blue hue components. Eight kinds of test stimuli in the natural color system (NCS) color notation system were used. These stimuli were presented at horizontal and vertical meridians, and at meridians inclined at 45° angles. The illuminance level was set at six levels: 0.01 lx-1000 lx. The evaluation method measured chromatic, white, and black components as well as the hue component of the stimuli. Results show that the color zone of the retina extended further into the periphery with increasing illuminance; the response of opponent colors y-b was shown to be greater than that of the opponent colors r-g. 相似文献
53.
A new optical technique based on real time holographic interferometry in true colors has been implemented around the transonic
wind tunnel of the ONERA-Lille center to analyze 2D unsteady wake flows. Tests realized in color interferometry, real time
and double exposure, use simultaneously three wavelengths of a continuous waves laser (argon and krypton mixed) and holograms
are recorded on silver-halide single-layer panchromatic Slavich PFG03c plates. The very principle of real-time true color
holographic interferometry uses three primary wavelengths (red, green and blue) to record, under no-flow conditions, the interference
among the three measurement beams and the three reference beams simultaneously on a single reference hologram. After the holographic
plate is developed, it is placed on the test setup again in the position it occupied during exposure and the hologram is illuminated
again by the three reference beams and three measurement beams. A flat, uniform color can then be observed behind the hologram.
So a horizontal, vertical, or even circular fringe pattern can be formed and the achromatic central fringe can be made out
very clearly. The single color is used to determine the path difference zero on the interferograms. The flow studied was the
unsteady flow downstream of a cylinder placed crosswise in the test section. A sequence of hundred interferograms was recorded
on the flow around the cylinder at Mach 0.37. The vortex formation and dissipation phases can be seen very clearly, along
with the fringe beat to either side of the cylinder. 相似文献
54.
The reversible nonlinear conduction (RNC) in of high‐density polyethylene/acetylene carbon black composites with different degrees of crosslinking was studied above room temperature and below the melting point of high‐density polyethylene (HDPE). The experimental current density‐electric field strength curves can be overlapped onto a master curve, suggesting that the microscopic mechanisms for the appearance of RNC exist regardless of the ambient temperature and the crosslinking degree of the HDPE matrix. The relationship between the crossover current density and the linear conductivity can be explained in the framework of the dynamic random‐resistor‐network model. According to these results, two electron‐tunneling models are suggested to interpret the microscopic conduction behavior. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 1212–1217, 2004 相似文献
55.
Nylon‐6/glass‐fiber (GF)/liquid‐crystalline‐polymer (LCP) ternary blends with different viscosity ratios were prepared with three kinds of nylon‐6 with different viscosities as matrices. The rheological behaviors of these blends were characterized with capillary rheometry. The morphology was observed with scanning electron microscopy and polarizing optical microscopy. This study showed that although LCP did not fibrillate in binary nylon‐6/LCP blends, LCP fibrillated to a large aspect ratio in some ternary blends after GF was added. The addition of 5 wt % LCP significantly reduced the melt viscosity of nylon‐6/GF blends to such an extent that some nylon‐6/GF/LCP blends had quite low viscosities, not only lower than those of neat resins and nylon‐6/GF blends but also lower than those of corresponding nylon‐6/LCP blends. The mutual influence of the morphology and rheological properties was examined. The great reduction of the melt viscosity was considered the result of LCP fibrillation. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 1619–1627, 2004 相似文献
56.
Based on the complexation between proteins and Cu(II) coupled with the time-resolved chemiluminescence (CL) technique, a highly sensitive and quantitative assay for measuring proteins in solution is described. The complexes of proteins with Cu(II) have a strongly catalytic effect on the luminol-H2O2 CL reaction. Because the CL emission produced by the complexes is much more long-lived than that by Cu(II), the CL signals originating from proteins can be easily identified and measured with a time-resolved technique. On this basis, bovine albumin fraction V (BAF V) can be quantitatively determined in the range of 0.01 - 5.0 microg/ml with a detection limit of 5.8 ng/ml. The results show that the proposed assay exhibits a small variation in the response values for the same amount of different proteins, as compared to the Lowry as well as Bradford assays. The CL assay has also been studied for the detection of immobilized proteins. 相似文献
57.
A hybrid cluster complex, formed by chelating a chromogenic ligand to a [2Fe-2S] cluster, sensitively exhibited differential colorimetric responses towards Hg2+, Cd2+, Cr3+, Pb2, Sn2+, Cu2+, Zn2+, Fe3+ and Co2+ in water at physiological pH. Speciation of some of these metal elements, such as Cr(III) and Sn(IV), was also studied by UV/Vis absorption. 相似文献
58.
59.
A New Triterpene from the Orchid Pholidota yunnanensis 总被引:2,自引:0,他引:2
ZhiMingBI ZhengTaoWANG LuoShanXU 《中国化学快报》2004,15(10):1179-1181
A new triterpene, 25-methylenecyclopholidonyl p-hydroxy-trans-cinnamate, was isolated from a orchid Pholidota yunnanensis. The structure elucidation and ^1H, ^13C-NMR assignments were achieved by spectral and chemical method. 相似文献
60.
Baker‘s yeast mediated reduction of optically active diketone is described. The two keto groups are efficiently differentiated and the ee value of the recovered material is considerably raised. It affords highly optically active key intermediates efficiently for the synthesis of natural polyhydroxylated agarofuran products. 相似文献