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991.
992.
Kensuke Fukuda Wataru Saito Shoichi Arai Yoshiro Aida 《Journal of the Institute of Brewing》1999,105(3):179-184
A proanthocyanidin-free (ant-free) barley with improved quality, Mokkei 92–130, was bred from the cross between Ant 13–347, an ant-free mutant and Haruna Nijo, a Japanese malting barley variety. The malting and brewing quality of the line are described in this paper, while its agronomic performance will be summarised elsewhere. Mokkei 92–130 achieved high levels in some malting quality character including hot water extract, diastatic power and apparent attenuation limit, which were significantly low in most of the ant-free lines and varieties previously reported. Cell wall degradation was also improved. Overall malting quality was found to be satisfactory in Mokkei 92–130. Pilot-scale brewing trials showed that Mokkei 92–130 had superior colloidal stability (less haze formed) in its final beer compared with the normal counterparts. Beer brewed with ant-free barley at a pilot-scale performed as well as the standard production in sensory evaluations soon after bottling, although it was rated poorer than the control after one month storage at ambient temperature. 相似文献
993.
Nishiyama N. Mizutani A. Hatori N. Arai M. Koyama F. Iga K. 《IEEE journal of selected topics in quantum electronics》1999,5(3):530-536
We have demonstrated an oxide confinement polarization controlled vertical-cavity surface-emitting laser (VCSEL) grown on a GaAs (311)B substrate. The polarization state was well controlled along the [2¯33] crystal direction due to an anisotropic gain in the (311)B plane. We fabricated a small oxide aperture VCSEL with a threshold of 260 μA and realized single-transverse mode and single-polarization operation for the first time. The sidemode suppression ratio (SMSR) was 35 dB and the orthogonal polarization suppression ratio (OPSR) was 25 dB. In addition, we have measured polarization and transverse mode characteristics of multi- and single-transverse mode devices under high-speed modulation. In the multimode device of 12 μm×12 pm oxide aperture, we have achieved stable polarization operation of over 25-dB OPSR up to 10 Gb/s and have observed no power penalty due to polarization instability under 2.5-Gb/s pseudorandom modulation. The single-mode device showed stable single-transverse mode and polarization under the modulation conduction up to 5 GHz of sinusoidal modulation. SMSR and OPSR were over 30 and 10 dB, respectively 相似文献
994.
Eiji Takahashi Akinori Ebe Kiyoshi Ogata Yoshinori Hayashi Daisuke Makabe Mototaka Sone 《Electrical Engineering in Japan》2000,131(4):11-18
Two different surface treatments (mechanical polishing, thin film deposition) were performed on cathode surfaces, and the field emission currents from the cathodes were measured with a microchannel plate. In order to discuss the relationship between the breakdown voltage and prebreakdown current in the vacuum gap, the breakdown voltage was measured after field emission measurement. The V–I characteristics of the field emission and breakdown voltage were influenced by surface treatment, and the breakdown voltages of mechanical polished cathodes were lower than those of the thin film deposited cathodes. It was found that the probability of breakdown increased when the field emission current reached 10–11 A. Atomic force microscope (AFM) measurements showed numerous protrusions on the cathode surface in the case of thin film deposition treatment, but we estimated by the finite element method that these protrusions make the field enhancement effect low. It was inferred that the breakdown voltage in vacuum gaps could be increased by the thin film deposition method. © 2000 Scripta Technica, Electr Eng Jpn, 131(4): 11–18, 2000 相似文献
995.
The phase behavior and reaction of nylon 6/6 in water were studied with a diamond anvil cell (DAC) technique and visual microscopy. Nylon 6/6 concentrations in water and cell temperatures were varied from 11 to 46% and from 264 to 425°C, respectively. The pressures studied ranged from 30 to 900 MPa. When an aqueous solution of 27% nylon 6/6 was rapidly heated (2.6°C/s) to 372°C at 30 MPa, the solution became homogeneous at 331°C. Upon cooling, the final pressure was 30 MPa and both particles and gas were observed. Analysis of the particles by Raman indicated decomposed nylon 6/6 solid. When an aqueous solution of 31% nylon 6/6 was rapidly heated (2.9°C/s) to 425°C at 58 MPa, the solution became homogeneous at 323°C. Upon cooling, the final pressure was 143 MPa, and, remarkably, only a second liquid precipitated and no gas or solids were observed. From the experiments, we concluded that the reaction pathways are completely different between the subcritical and supercritical water conditions. For the case of subcritical conditions, the final products were solid particles having a nylon character along with a considerable amount of gas. At supercritical water conditions, the final products were liquids having little nylon character and no gas. Experiments were performed at a constant temperature of 272°C at initial pressures ranging from 87 to 400 MPa. As the reaction proceeded, the pressure was measured at 30‐s intervals. At average pressures less than 300 MPa, the nylon 6/6 samples melted and appeared to become homogeneous. At average pressures higher than 520 MPa, the nylon 6/6 samples remained heterogeneous. From these results, the rate of hydrolysis was concluded to increase with pressure. The reaction volume was found to be −21.1 cm3/mol, which can be explained by the overall formation of water‐soluble products. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 1062–1073, 2000 相似文献
996.
Hiroki Sano Kentaro Sato Kiyoshi Ohishi Toshimasa Miyazaki 《Electrical Engineering in Japan》2013,184(3):36-46
It is desirable for a container crane to operate smoothly and quickly. For this purpose, the control system of a container crane should be capable of antisway control for suppressing vibrations. A vision sensor system is often used to detect the sway angle. However, since a control system with a vision sensor has a delay time when determining the angle, it sometimes leads to deterioration of control performance owing to the delay time. In order to overcome this problem, this paper proposes a new antisway crane control system based on a dual‐state observer with sensor‐delay correction. However, because of nonlinear friction in the crane, the estimation accuracy achieved by using the observer is poor. To overcome this problem, this paper proposes a disturbance observer considering friction disturbance. The control performance and e?ectiveness of the proposed robust control system based on the estimated information are shown to be satisfactory by experimental results. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 184(3): 36–46, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22412 相似文献
997.
K Ueyama M Yokode H Arai Y Nagano ZX Li M Cho T Kita 《Canadian Metallurgical Quarterly》1998,24(1):182-190
OBJECTIVE: The aim was to investigate the consequences of simultaneous stimulation of phospholipase C and D by agonists for the molecular species composition of 1,2-diacylglycerol and phospholipids in cardiomyocytes. METHODS: Serum-free cultured neonatal rat cardiomyocytes were stimulated by endothelin-1, phenylephrine or phorbolester. The molecular species of 1,2-diacylglycerol (in mol%) and those derived from phosphatidylcholine and phosphatidylinositol were analyzed by high-performance liquid chromatography and their absolute total concentration (nmol per dish) by gas-liquid chromatography. Phospholipids were labelled with [14C]glycerol or double-labelled with [14C]16:0 and [3H]20:4n6 for measurements of respectively, the amount of or relative rate of label incorporation into 1,2-diacylglycerol. RESULTS: The major molecular species of 1,2-diacylglycerol in unstimulated cells was found to be 18:0/20:4 (57 mol%). The same species was observed predominantly in phosphatidylinositol (73 mol% compared to 11 mol% in phosphatidylcholine). A significant decrease (about 10 mol%) was found for the 18:0/20:4 species of 1,2-diacylglycerol during stimulation (10-40 min) with endothelin-1 or phorbolester, but not phenylephrine. The results of the double-labelling experiments were consistent with the latter finding: the ratio [3H]20:4 over [14C]16:0 in 1,2-diacylglycerol decreased from 1.70 in the control to 1.40 during 10-min endothelin-1 or phorbolester stimulation, but not during phenylephrine stimulation. The [14C]glycerol incorporation into 1,2-diacylglycerol remained relatively constant under agonist-stimulated conditions as did the total concentration of 1,2-diacylglycerol. CONCLUSIONS: 1,2-Diacylglycerol present in unstimulated cardiomyocytes is likely derived from phosphatidylinositol. During stimulation with endothelin-1 and phorbolester, but not phenylephrine, phosphatidylcholine becomes an increasingly important source for 1,2-diacylglycerol due to sustained activation of phospholipase D. The 1,2-diacylglycerol level remains relatively constant during agonist stimulation which strongly indicates that particular molecular species of 1,2-diacylglycerol more than its total concentration determine the activation of protein kinase C isoenzymes. 相似文献
998.
Spatially detailed survey on pollution by multiple perfluorinated compounds in the Tokyo Bay basin of Japan 总被引:1,自引:0,他引:1
Zushi Y Ye F Motegi M Nojiri K Hosono S Suzuki T Kosugi Y Yaguchi K Masunaga S 《Environmental science & technology》2011,45(7):2887-2893
Pollution from 35 perfluorinated compounds (PFCs) in the water of the Tokyo Bay basin was examined. The water in the basin contained relatively high levels of perfluorononanoate (PFNA), perfluorooctanoate (PFOA), and perfluorooctane sulfonate (PFOS) compared to the other PFCs, which were present at concentrations of 20.1 ng/L, 6.7 ng/L, and 5.8 ng/L, respectively. In contrast, the concentrations of their precursors and degradation products were an order of magnitude lower. Sewage treatment plant (STP) effluent in the area also contained high levels of PFNA compared with the river water samples (Mann-Whitney U-test, p<0.0002). From a spatial aspect, increases in PFC pollution levels correlated with increased urbanization in the study area suggested that there are nonpoint source contributors to the PFC pollution in this area. Branched isomers of the PFCs were also quantified. Samples that contained high concentrations of perfluoroalkyl carboxylates (PFCA) showed lower proportions of its branched isomer. This indicates that the branched isomers are more prominent in the area with lower PFC pollution. This analysis was beneficial for estimating the individual contributions of different PFCA production processes. This survey provided new information on the sources, spatial distribution, and behavioral characteristics of PFC pollutants in this area. 相似文献
999.
Kosuke Arai Satoshi Murata Taifeng Wang Wataru Yoshimura Mayumi Oda-Tokuhisa Tadashi Matsunaga David Kisailus Atsushi Arakaki 《International journal of molecular sciences》2022,23(10)
Biomineralization is an elaborate process that controls the deposition of inorganic materials in living organisms with the aid of associated proteins. Magnetotactic bacteria mineralize magnetite (Fe3O4) nanoparticles with finely tuned morphologies in their cells. Mms6, a magnetosome membrane specific (Mms) protein isolated from the surfaces of bacterial magnetite nanoparticles, plays an important role in regulating the magnetite crystal morphology. Although the binding ability of Mms6 to magnetite nanoparticles has been speculated, the interactions between Mms6 and magnetite crystals have not been elucidated thus far. Here, we show a direct adsorption ability of Mms6 on magnetite nanoparticles in vitro. An adsorption isotherm indicates that Mms6 has a high adsorption affinity (Kd = 9.52 µM) to magnetite nanoparticles. In addition, Mms6 also demonstrated adsorption on other inorganic nanoparticles such as titanium oxide, zinc oxide, and hydroxyapatite. Therefore, Mms6 can potentially be utilized for the bioconjugation of functional proteins to inorganic material surfaces to modulate inorganic nanoparticles for biomedical and medicinal applications. 相似文献
1000.
We have fabricated graphene/graphene oxide/graphene (G/GO/G) junctions by local anodic oxidation lithography using atomic force microscopy (AFM). The conductance of the G/GO/G junction decreased with the bias voltage applied to the AFM cantilever V(tip). For G/GO/G junctions fabricated with large and small |V(tip)|. GO was semi-insulating and semiconducting, respectively. AFM-based LAO lithography can be used to locally oxidize graphene with various oxidation levels and achieve tunability from semiconducting to semi-insulating GO. 相似文献