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111.
Fluorine compounds have high discharge voltage due to its highly ionic metal-ligand bonds. In them, perovskite-type metal trifluorides with corner sharing matrix have large bottlenecks of diffusion pathways for intercalants. Iron trifluoride composites (FeF3-C) prepared by planetary ball milling with carbon showed reversible charge/discharge behavior not only for Li, but also for Na anodes. X-ray diffraction and 57Fe Mössbauer spectroscopy were applied to characterize the electrochemical properties of FeF3 vs. Li and Na anodes. The cathode performances of the other commercially available transition metal trifluorides such as MF3 (M = Ti, V, Mn, Co) have been also investigated.  相似文献   
112.
Reaction between epoxidized natural rubber and poly(L ‐lactide) (PLLA) was investigated quantitatively in terms of conversion of the epoxidized natural rubber. The epoxidized natural rubber was prepared by epoxidation of high ammonia natural rubber (HA‐NR) or deproteinized natural rubber (DPNR) with peracetic acid followed by depolymerization with ammonium persulfate. The resulting liquid HA‐NR having epoxy group (LENR) or liquid DPNR having epoxy group (LEDPNR) were subjected to heating at 473 K for 20 min, after blending with PLLA. The products were characterized through morphology observation, DSC measurement, and 1H‐NMR spectroscopy. The conversions of the rubbers were estimated from intensity ratio of signals in 1H‐NMR spectrum for the products after removing unreacted rubber with toluene. Difference in the estimated conversion between the LENR/PLLA and LEDPNR/PLLA blends was interpreted in relation to proteins present in the rubber. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   
113.
Er2O3 is candidate material for insulating coating to prevent the magnetohydrodynamic (MHD) pressure drop in the self-cooled liquid Li blanket system. Although Er2O3 is stable material, detailed chemical behavior in liquid Li is not clear. Corrosion behavior of bulk Er2O3 in Li is investigated in static and flowing condition in the present study. After these tests, good compatibility of Er2O3 was confirmed and slight formation of LiErO2 was detected by XRD analysis. This chemical behavior did not change in a static and flowing tests, however some of the corrosion product of LiErO2 was removed easily by the Li flow. Intensity of LiErO2 peaks in XRD spectrum suggests that the temperature gradient may affect the reaction rate in the natural convection loop. Since corrosion rate of Er2O3 is very small, slight change in state will be important information to evaluate lifetime of coating.  相似文献   
114.
We determined phase equilibria in the Co-rich Co-Al-W-Ti quaternary system at a temperature range between 900 °C and 1200 °C with a close attention to the thermodynamic stability of the γ′-Co3(Al, W, Ti) (L12) phase, based on micro-structure observation and electron microprobe analysis on bulk alloy samples heat-treated for periods up to 2000 h. In the quaternary system the single phase field of γ′ extends from the Co-Ti binary edge to a composition of Co-5Al-8.5W-8Ti (in at.%) at 900 °C. At the tip of the single phase field, the γ′ phase is in equilibrium with the γ-Co (A1), Co2AlTi (L21) and Co3W (D019) phases. The constructed vertical section of phase diagram between Co-9.4Al-9.6W and Co-16.5Ti indicates that there is a narrow composition range around Co-4.5Al-5.4W-7.5Ti in which the γ single phase field exists at high temperatures above 1200 °C and two-phase of γ+γ′ is thermodynamically stable at low temperatures below 1100 °C.  相似文献   
115.
In-flight particle measurements of the surface temperature and velocity are important for understanding of melting behavior of glass particles during in-flight melting by multi-phase AC arc plasma. However, the use of optical pyrometry for particle surface temperature has inevitable uncertainties due to non-thermal emissions signals from the plasma plume. This work presents spectroscopic measurements of the non-thermal signals which were found to be caused mainly by the plasma emissions scattered by the particles and the radiation emitted by vapor. After that, the accuracy of thermal radiation measurement was estimated and surface temperature of in-flight glass particle was corrected.  相似文献   
116.
Ionic liquid is a kind of salt that stays in a molten state even at room temperature. It does not vaporize at all in vacuum and facilitates electrical conductivity to the sample surfaces for observations with a scanning electron microscope (SEM). In this study, we used an ionic liquid in SEM for the first time to observe fixed human culture cells. The condition for the cell culture using wrapping sheets and SEM settings were varied to elucidate the optimized protocol. Compared to samples prepared by the conventional way, the ionic liquid‐treatment of samples gave SEM images of the cellular ultra structures in more detail, enabling observation of microvilli that made bridges between separated cells. In addition, the ionic liquid treatment is less time consuming as well as less laborious compared with the conventional way that includes dehydration, drying, and conductivity treatments. Totally, we concluded the ionic liquid is a useful reagent for SEM sample preparation. Microsc. Res. Tech., 2011. © 2010 Wiley‐Liss, Inc.  相似文献   
117.
在高60cm,宽45cm 的模拟电子装置内,进行装置内热移动研究,得到不同条件下的温度分布及速度分布.在理论解析及数值计算基础上,进行无因次准数关联,得出实验式.实验结果及解析结果基本一致.利用所得实验式对正在运转或有待开发的新的电子装置有关参数进行推算,对于传热设计具有很强的实用性.  相似文献   
118.
Suzuki T  Yazawa T  Sasaki O 《Applied optics》2002,41(10):1972-1976
We describe an interferometer system that uses two separate wavelengths to measure step height. The overlapping interference images detected by a CCD camera are easily separated by an ordinary integrating-bucket method and time-sharing sinusoidal phase modulation, in which two laser diodes are alternately modulated with a sinusoidal signal. A phase map is obtained only for the laser diode into which the modulation signal is injected. In this instance, a 1-microm step height was accurately detected.  相似文献   
119.
Organosilane self-assembled monolayers (SAMs) have been applied to resist materials for nanolithography based on scanning probe microscopy. An organosilane SAM was prepared on Si substrates from a precursor, that is octadecyltrimethoxysilane. Using an atomic force microscope with a conductive probe, current was injected from the probe into the SAM-covered Si substrate so that the SAM was locally degraded at the probe-contacting point. Nanoscale patterns drawn on the SAM was clearly imaged by lateral force microscopy. The patterning could be conducted in air while, in vacuum at the order of 10(-6) Torr, no detectable patterns were fabricated. The presence of adsorbed water at the probe/sample junction was confirmed to be crucial for the patterning of the SAM/Si. Its mechanism was, thus, ascribed to electrochemical reactions of both the SAM and Si with adsorbed water.  相似文献   
120.
Model-based learning systems such as neural networks usually “forget” learned skills due to incremental learning of new instances. This is because the modification of a parameter interferes with old memories. Therefore, to avoid forgetting, incremental learning processes in these learning systems must include relearning of old instances. The relearning process, however, is time-consuming. We present two types of incremental learning method designed to achieve quick adaptation with low resources. One approach is to use a sleep phase to provide time for learning. The other one involves a “meta-learning module” that acquires learning skills through experience. The system carries out “reactive modification” of parameters not only to memorize new instances, but also to avoid forgetting old memories using a meta-learning module.This work was presented, in part, at the 9th International Symposium on Artificial Life and Robotics, Oita, Japan, January 28–30, 2004  相似文献   
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