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91.
92.
The deposition of chlorophyll-a monolayers onto an SnO2 optically transparent electrode was studied in relation to the deposition ratio. The values of the deposition ratio, which were approximately 0.95 for the upward movement and very small but non-zero for the downward movement, suggest that the multilayers prepared are Z-type films containing a small fraction of the Y-type component corresponding to the non-zero value. This is consistent with the photo- electrochemical behaviour of the pigmented electrodes which is markedly dependent on the deposition ratios, indicating structural inhomogeneity or imperfection of the multilayers. 相似文献
93.
The high temperature transition in U4O9 has been studied by electrical conductivity measurements and X-ray diffraction. From the electrical conductivity measurements, a similar variation of log σ with reciprocal temperature to that in the transition range near room temperature is observed in the temperature range from about 300 to 800°C. Like the low temperature transition, a small lattice contraction is also observed in that temperature range by means of X-ray diffractometry, and the transition temperature increases from 530 to 620°C with increasing O/U ratio. After the transition the intensity of superlattice reflections increases, but that of superlattice reflections disappears. The mechanism of this high temperature transition is considered to be a second-order transition of the order—disorder type based on the configurational change of U4+ and U5+ with the shift of some portions of the lattice oxygen atoms from the lattice sites to the interstitial positions. The phase diagram of U4O9 is presented on the basis of the electrical conductivity and X-ray data. 相似文献
94.
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96.
Late asthmatic response causes peripheral airway hyperresponsiveness in dogs treated with metopirone
S Itabashi T Ohrui K Sekizawa T Aikawa H Nakazawa H Sasaki 《Canadian Metallurgical Quarterly》1993,101(2):215-220
To determine if late asthmatic response (LAR) is associated with hyperresponsiveness of airway smooth muscle itself, we performed antigen challenge in dogs treated with Metopirone. We studied the contractile response to acetylcholine (ACh) in isolated bronchial and bronchiolar segments 8 h after either saline inhalation (the control group) or antigen challenge in dogs demonstrating immediate asthmatic response (IAR) alone and in dogs demonstrating both IAR and LAR. Airway responses to Ascaris suum antigen were assessed by changes in respiratory resistance measured with the forced oscillation technique at 3 Hz. Concentration-response curves of bronchial preparations to ACh did not differ significantly among three groups consisting of the control, IAR and LAR. However, the contractile response of bronchiolar preparations to ACh was significantly greater in the LAR group when compared to the control and IAR groups at the concentrations of ACh ranging from 10(-6) to 3 x 10(-4) M (p < 0.01). SQ 29548, a receptor antagonist of thromboxane A2 and prostaglandin D2 (PGD2), inhibited LAR-induced hyperresponsiveness to ACh in a concentration-dependent fashion. The bronchiolar preparations obtained from dogs showing LAR contained a significantly higher amount of PGD2 than those obtained from dogs showing IAR alone (p < 0.01, n = 6). These results suggest that LAR is associated with hyperresponsiveness of peripheral airway smooth muscle to ACh, and this augmented response to ACh mediates via PGD2 released during LAR. 相似文献
97.
Masaki Saito Nobuo Yamaoka Keiji Miyazaki Masahiko Kinoshita Yoshihito Abe 《Nuclear Engineering and Design》1994,146(1-3)
To study the effects of reduced gravity on the flow regime and the heat transfer characteristics of a boiling two-phase horizontal flow, parabolic flight experiments were performed by using an aircraft. The gravity level during the parabolic flight and the duration time were about −0.01ge +0.01ge and 20 s, respectively. Under earth gravity, many small bubbles are detached very frequently from the heater rod surface, flowing into the upper stream due to the buoyancy and resulting in a stratified flow in the cases of lower inlet fluid velocity and higher heat flux. Under microgravity conditions, bubbles are hardly detached from the heater rod, growing and coalescing to become much larger along the heater rod, surrounding the heater rod in the downstream. This tendency was more noticeable in the cases of lower inlet fluid velocity, higher heat flux and lower inlet fluid subcooling. The local heat transfer coefficients at the bottom of the heater rod tend to decrease slightly under microgravity compared with those under earth gravity because of the reduction of the heat removal due to natural convection. On the other hand, the local heat transfer coefficients at the top of the heater rod tend to increase slightly under microgravity. However, the differences of the local heat transfer coefficients are very small in spite of large differences of the flow regimes under earth gravity and microgravity. 相似文献
98.
Keiji Katsuno Akihiro Nishioka Tomonori Koda Ken Miyata Go Murasawa Yoshiko Nakaura Naoyoshi Inouchi 《Starch - St?rke》2010,62(9):475-479
The present study investigated a novel milling method for producing amorphous rice starch without adding water. A new type of milling machine was developed (termed the shear and heat milling machine (SHMM)), which is capable of applying mechanical shear and heat during the milling process. The SHMM consisted of a pair of rice mortars attached to a servomotor and a ring heater. The heater was installed on the upper mortar; the temperature of the upper mortar was monitored and controlled by a thermal controller. Wide‐angle X‐ray diffraction (WAXD) analysis was used to determine the crystallinities of starch in rice flour samples produced using the SHMM at different milling temperatures. The WAXD data for milled rice flour that had been heated exhibited no diffraction peaks. This experimental result demonstrates that the developed SHMM produces amorphous rice starch easily by milling with heating without the addition of water. The milling conditions such as the shear and heat applied can be used to control the crystallinity of starch in rice. 相似文献
99.
Kenta Inagaki Takatoshi Hijikata Takeshi Tsukada Tadafumi Koyama Keiji Ishikawa Shoichi Ono 《Journal of Nuclear Science and Technology》2014,51(7-8):906-915
A simulation code was developed to evaluate the performance of the cesium adsorption instrument operating in Fukushima Daiichi Nuclear Power Station. Since contaminated water contains seawater whose salinity is not constant, a new model was introduced to the conventional zeolite column simulation code to deal with the variable salinity of the seawater. Another feature of the cesium adsorption instrument is that it consists of several columns arranged in both series and parallel. The spent columns are replaced in a unique manner using a merry-go-round system. The code is designed by taking those factors into account. Consequently, it enables the evaluation of the performance characteristics of the cesium adsorption instrument, such as the time history of the decontamination factor, the cesium adsorption amount in each column, and the axial distribution of the adsorbed cesium in the spent columns. The simulation is conducted for different operation patterns and its results are given to Tokyo Electric Power Company (TEPCO) to support the optimization of the operation schedule. The code is also used to investigate the cause of some events that actually occurred in the operation of the cesium adsorption instrument. 相似文献
100.
YanXin Dan Takashi Costa Atsushi Nakamura Keiji Komatsu Hidetoshi Saitoh 《Ceramics International》2021,47(9):11862-11869
The morphology and microstructure of splats impact the comprehensive capability of a new coating methodology called chelate flame spraying (CFS). This study addresses the quantitative characterization of the spread morphologies of flame sprayed Er2O3 splats directly deposited under different spray conditions on aluminum alloy substrates with a mirror finish. The influence of the in-flight particle temperature and velocity, carrier gas type, and carrier gas ratio on the solidification mechanism of molten droplets was investigated. Image analysis methods were employed to identify single splats from the morphology observed with field-emission scanning electron microscopy (FE-SEM). In addition, Er2O3 films were synthesized on an Al–Mg alloy (A5052) substrate using N2 or O2 as the carrier gas. When O2 was used as the carrier gas, 109-μm-thick films were deposited on the A5052 substrate. The cross-sectional porosity of the films was 3.8%. In contrast, films with 101-μm thickness were synthesized on the A5052 substrate when N2 was used as the carrier gas. The cross-sectional porosity of these films was 13.8%. The results showed that the carrier gas type (N2) and carrier gas ratio had a significant effect on the flattening behavior of the molten droplets. A spraying method combined with multidimensional modes is proposed to control the morphology of the splats. 相似文献