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71.
M. Takahashi H. Sofue T. Iguchi M. Matsumoto F. Huang Y. Pramono T. Matsuzawa S. Uchida 《Progress in Nuclear Energy》2005,47(1-4):553-560
For the development of 45w%Pb-55w%Bi cooled direct contact boiling water small fast reactor (PBWFR), experimental study on Pb-Bi-water direct contact boiling two-phase flow has been performed using Pb-Bi-water direct contact boiling two-phase flow loop. For stable start-up of the boiling flow operation, Pb-Bi single-phase natural circulation must be realized in a Pb-Bi flow system of the loop before water injection into Pb-Bi. The Pb-Bi flow system consists of a four-heater-pin bundle, a chimney, an upper plenum, a level meter tank, a cooler, and an electromagnetic flow meter. A stable Pb-Bi single-phase natural circulation was realized in the range of flow rate from 1.5 l/min to 4.8 l/min by heating Pb-Bi in the heater-pin bundle with a power up to 7.7 kW. The inlet and outlet temperatures of the heater bundle were in the ranges from 243°C to 278°C, and from 251°C to 278°C, respectively. The natural circulation flow was simulated analytically using one-dimensional flow model including frictional, form and drag forces. Total hydraulic head through the loop were calculated from Pb-Bi densities at measured Pb-Bi temperatures in the loop. It was found that the calculated flow rate agreed well with the measured ones, which indicated the validity of the analytical models. 相似文献
72.
Baku Katagiri Tetsuya Miyashita Takahiro Ishinabe Tatsuo Uchida 《Journal of the Society for Information Display》2003,11(3):585-590
Abstract— One problem with front‐projection displays is that the screen contrast ratio decreases in bright ambient light. In this paper, we propose a new front‐projection display system that incorporates the control of reflection of ambient light in the screen design, providing a high contrast ratio even in a brightly lit room. 相似文献
73.
Palilis L.C. Uchida M. Kafafi Z.H. 《IEEE journal of selected topics in quantum electronics》2004,10(1):79-88
We report on electron injection from two different metal electrodes into three silole derivatives, namely 2,5-di-(3-biphenyl)-1,1-dimethyl-3,4-diphenylsilacyclopentadiene (PPSPP), 1,2-bis(1-methyl-2,3,4,5,-tetraphenylsilacyclopentadienyl) ethane (2PSP) and 2,5-bis-(2', 2'-bipyridin-6-yl)-1, 1-dimethyl-3,4-diphenylsilacyclopentadiene (PyPySPyPy), previously employed as emissive and electron transport materials in molecular organic light-emitting diodes (MOLEDs). Silole films were sandwiched between symmetric Mg:Ag or bilayer CsF-Al electrodes. The steady-state current density-voltage characteristics were measured as a function of the silole layer thickness for the two cathodes. The trap-free space-charge-limited current based on time-of-flight measurements compared with the injected electron current for PyPySPyPy indicated that Mg:Ag contacts limit the injected current, while CsF-Al contacts behave as quasi-ohmic contacts. Similar findings were obtained for 2PSP and PPSPP allowing steady-state derived electron mobility parameters to be extracted. Based on space-charge-limited conduction analysis of the measured current-voltage characteristics, PyPySPyPy is found to be a superior electron transporting silole with approximately an order of magnitude higher electron mobility (2.0/spl times/10/sup -4/ cm/sup 2//Vs) compared with those of 2PSP (2.4/spl times/10/sup -5/ cm/sup 2//Vs) and PPSPP (5.2/spl times/10/sup -5/ cm/sup 2//Vs), which is significantly higher than that of the prototype electron transport material tris (8-hydroxyquinolinolato) aluminum (III) (Alq/sub 3/) (6.5/spl times/10/sup -7/ cm/sup 2//Vs) at 0.6 MV/cm. 相似文献
74.
75.
Kubany Edward S.; Hill Elizabeth E.; Owens Julie A.; Iannce-Spencer Cindy; McCaig Mari A.; Tremayne Ken J.; Williams Paulette L. 《Canadian Metallurgical Quarterly》2004,72(1):3
This article describes a second treatment-outcome study of cognitive trauma therapy for battered women with posttraumatic stress disorder (PTSD; CTT-BW). CTT-BW includes trauma history exploration: PTSD education; stress management; exposure to abuse and abuser reminders; self-monitoring of negative self-talk; cognitive therapy for guilt; and modules on self-advocacy, assertiveness, and how to identify perpetrators. One hundred twenty-five ethnically diverse women were randomly assigned to immediate or delayed CTT-BW. PTSD remitted in 87% of women who completed CTT-BW, with large reductions in depression and guilt and substantial increases in self-esteem. White and ethnic minority women benefited equally from CTT-BW. Similar treatment outcomes were obtained by male and female therapists and by therapists with different levels of education and training. Gains were maintained at 3- and 6-month follow-ups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
76.
Abstract— Viewing‐angle dependences of the contrast ratio and color shift of LCDs have been radically improved as evidenced by the increasing application of LCDs in high‐quality television. This paper describes the concept of optical compensation and the fundamental characteristics of the viewing‐angle property for various LC modes. 相似文献
77.
Improvement of lysozyme recovery method from the precipitate of protein-anionic surfactant complexes
Takumi Kinugasa Kanako Okabe Kenta Jinno Kiyohito Uchida Yasuhiro Nishii 《分离科学与技术》2017,52(18):2918-2925
A new protein separation process using a surfactant and a polar organic solvent consists of a precipitation step and a recovery step. In the precipitation step, a protein-surfactant complex is precipitated from an aqueous solution, when an ionic surfactant, sodium di(2-ethylhexyl) sulfosuccinate (AOT), is added to an aqueous solution, including protein (lysozyme). In the recovery step, the precipitate is dissolved in a polar organic solvent, such as acetone, and the protein is recovered as precipitates when a very small amount of salt solution was added to remove surfactants from the protein-surfactant complex. However, the details of the protein recovery step from precipitate have not been studied yet. In this study, the improvement of the protein recovery step was examined from the viewpoint of a recovery ratio of protein and a remaining ratio of surfactant. The optimum NaCl concentration in the feed for the protein recovery was in the range of 0.05–0.2 kmol/m3. As the NaCl concentration in the feed increased to more than 0.2 kmol/m3, the precipitation ratio decreased due to the electrostatic screening effect of NaCl. It was found that the addition of a very small amount of NaCl solution to acetone was unnecessary when NaCl was included in the feed lysozyme solution. On the other hand, as the NaCl concentration decreased to less than 0.05 kmol/m3, the precipitation ratio was decreased due to the low re-precipitation of protein by the addition of a small amount of NaCl solution in acetone. In the case of the feed containing no salt, the desired NaCl concentration added to acetone was in the range above 0.2 kmol/m3. In addition, the most suitable volume ratio of acetone to feed was found to be 0.2. 相似文献
78.
Abstract Baseball pitching requires contributions from and interaction among all limb segments. Most previous investigators have concentrated on the throwing arm itself, but the center of mass (COM) and contribution of all segments in the pitching motion have not been studied. The purpose of this study was to investigate the momentum transfer of all body segments in the pitching motion. The kinematics pitching motion data were captured from three experienced pitchers (one is professional, two are amateurs). A ten‐segment body system was modeled in this study. The results showed that the lowest position of the COM during the pitching cycle occurred around the ball release time and the fastest velocity (2.81±0.18 m/sec) of the COM was in the late cocking phase. The trunk and thigh on the throwing side showed the largest linear momentum among all segments in the late cocking phase. The upper throwing arm and forearm had peak linear momentum in the acceleration phase. The trunk also had the largest angular momentum during the pitching cycle and reached the maximum rotational momentum (4.17±1.22 Kg‐m2/sec) in the late cocking phase and medial bending momentum (9.03±5.78 Kg‐m2/sec) at the end of the late cocking phase. From the time sequence of linear momentum changes, especially in the leading direction, the force transfer from the foot to the trunk then through the upper extremity during the pitching motion was identified. The largest change rate of angular momentum found in the trunk meant that the trunk contributed the largest torque in the pitching motion. Better coordination of the body segments in the pitching motion not only enhances performance but also avoids injury. The coordination of motion by athletes in the pitching motion provides a guideline for better coaching and training. 相似文献
79.
Jan Westerink Gideon R. Hajer Mariëtte E. G. Kranendonk Henk S. Schipper Houshang Monajemi Eric Kalkhoven Frank L. J. Visseren 《Lipids》2014,49(3):247-254
We investigated the postprandial changes in plasma levels of adipocytokines in overweight patients with metabolic syndrome after an oral fat load. After an oral fat load and during a prolonged fast, blood was drawn at 0, 2, 3, 4 and 8 h for measurement of adiponectin, adipsin, cathepsin S, chemerin, hepatic growth factor, interferon‐γ‐inducible protein‐10, leptin, macrophage chemoattractant protein‐1, macrophage migration inhibitory factor, nerve growth factor, retinol binding protein‐4, resistin, serum amyloid A1, tissue inhibitor of metalloproteinase‐1 and thrombopoietin using a microbead‐based Luminex assay. Area under the curves (AUC) were calculated and compared. Plasma adiponectin levels were higher after an oral fat load compared to fasting at t = 2 h (950 ± 513 vs. ?1,881 ± 713 ng/ml) while the plasma levels for adipsin (?9 ± 5 vs. 16 ± 5 ng/ml), chemerin (?122 ± 35 vs. 13 ± 21 ng/ml), SAA‐1 (?391 ± 213 vs. 522 ± 173 ng/ml) and TPO (?335 ± 144 vs. 622 ± 216 ng/ml) were lower after an oral fat load compared to fasting. The baseline corrected AUC for IP‐10 was higher after fat load compared to fasting (median ?116 pg h/ml; IQR ?270 to 10 vs. ?21 pg h/ml; IQR ?136 to 418 (p = 0.047). In conclusion, in overweight male subjects with the metabolic syndrome, an oral fat load is accompanied with a modest anti‐inflammatory response of adipose tissue‐derived adipocytokines. 相似文献
80.
Mari K. N?ss Gabriella Tranell Jan Erik Olsen Nils Eivind Kamfjord Kai Tang 《Oxidation of Metals》2012,78(3-4):239-251
During oxidative ladle refining (OLR) of silicon, the metal surface is partly oxidized, resulting in the formation of a condensed silica fume (SiO2). This fugitive emission of silica represents a potential health hazard to the workers in the silicon and ferrosilicon industry. In the current work, industrial measurement campaigns aimed at recording the fume generation during OLR were performed at the Elkem Salten plant in Norway. The measured amounts of silica produced were 2.5–5.1?kg/h, depending on the gas flow rate in the refining process. The rate of silica production correlates with the total flow rate and amount of air in the purge gas, and increases as the flow rate increases. The results of this work suggest that fume generation during OLR primarily results from oxidation of the exposed metal surface, with oxygen transport from the surrounding atmosphere to the metal surface being the limiting factor. Other identified mechanisms of SiO2 formation were splashing of the metal and/or oxidation of SiO gas carried with the refining purge gas. 相似文献