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101.
Silica particles dispersed in liquid crystals exhibit a novel behavior such as a unique migrating behavior and alignment. These characteristics are found to depend on the size of the nanoparticles, the surface state of nanoparticles, the liquid crystal (LC) phases, the amplitude and the frequency of applied voltage. These are discussed in terms of anisotropic particle-particle and particle-LC molecules interactions in the anisotropic environment of liquid crystal matrix  相似文献   
102.
Transmission characteristics of arrayed waveguide gratings (AWGs) are significantly influenced by phase errors in a waveguide array, which are easily caused by the variation of fabrication process. In this paper, the statistical analysis of transmission characteristics is presented using correlation and spectral density of phase errors. A simple statistical approach, based on a simplified model of a waveguide array, is newly introduced to clarify statistical behavior of phase errors in AWGs. Spectral density is modeled from measured phase errors, and then average transmission characteristics are simulated for AWGs with different channel spacing. Average transmission characteristics, simulated with the spectral density model, almost describe measured results in the cases of various channel spacing. It is also indicated that an AWG may have larger adjacent-channel crosstalk with narrower channel spacing because the adjacent-channel crosstalk is affected by phase errors with a smaller spatial frequency.  相似文献   
103.
A quantification system for lysophospholipids (lysoPL) was developed, especially for blood samples, using liquid chromatography–tandem mass spectrometry (LC–MS/MS). However, the lysoPL measurement in cerebrospinal fluid (CSF) has not been validated. Therefore, the present study aimed to validate the lysoPL measurement using CSF samples and to elucidate the possible clinical significance of the lysoPL measurement in CSF. For the validation, we observed a good precision and linearity in a sample with high lysoPL levels. The concentrations of lysoPL changed after incubation but the changes were smaller than those observed for serum samples. Moreover, we observed that the CSF levels of 16:0, 18:0 lysophosphatidylcholine, and 18:0, 18:1, and 20:4 lysophosphatidic acid were significantly higher in subjects with central nervous system invasion caused by hematological malignancies or carcinoma than in subjects with no abnormal CSF test results. In conclusion, an LC–MS/MS quantification system for lysoPL in CSF might be useful and could be applied to clinical laboratory testing.  相似文献   
104.
The reaction of isocyanate in pressure sensitive adhesive (PSA) films adhered on to various adherends having different surface tensions was monitored by depth profiling using attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy.In the latter stages of crosslinking reaction, unreacted isocyanate and its derivatives exist more in the bulk of the PSA than in the interfaces between PSA and adherends which are Teflon sheet and PE film having relatively lower surface tensions. In the case of using stainless steel having relatively higher surface tension as adherend, opposite segregation was observed compared to Teflon and PE.From X-ray photoelectron spectroscopy (XPS), it was revealed that N atoms exist more in surface than in bulk when stainless steel is used as adherend. We conclude that polyisocyanates migrate in the PSA film in order to minimize the magnitude of interfacial free energy between the PSA and the adherend, which leads to the change of surface tension of PSA film.  相似文献   
105.
Space charge behavior in low density polyethylene at pre-breakdown   总被引:1,自引:0,他引:1  
It has been known that the electrical breakdown of insulating materials is strongly affected by the formation of space charge in the bulk of the materials. Many researchers have attempted to study the relationship between the space charge and the breakdown; however, it has not been clarified yet. Although the pulsed electroacoustic (PEA) method has been widely used to observe space charge profiles, previous works have not shown clear evidence of the influence of the space charge on the breakdown. Therefore, we have developed a new PEA system with an interval of 0.5 ms to observe the space charge distribution continuously under the ultra-high electric field. Using this system, we observed the space charge dynamics in the low-density polyethylene (LDPE) at and around the breakdown. We also investigated the dependence of the applied electric field on space charge behavior. From the results, it is found that the injected charge packet moved faster and deeper under a relatively lower electric field rather than that under a higher electric field. Furthermore, we found that the maximum electric field in each specimen was almost the same when the breakdown happened in a specimen.  相似文献   
106.
This paper deals with a strategic issue in the stable marriage model with complete preference lists (i.e., a preference list of an agent is a permutation of all the members of the opposite sex).  相似文献   
107.
108.
A major allergenic protein of buckwheat, Fag e 1 prepared from common buckwheat (Fagopyrum esculentum), was covalently linked with food-grade polysaccharides, arabinogalactan or xyloglucan through the controlled dry-heating at 60 °C under 65% relative humidity. The introduction of polysaccharide chain onto the molecular surface of Fag e 1 reduced the allergenicity of Fag e 1. The results revealed that the Maillard-type glycosylation of Fag e 1 with polysaccharides brought about a drastic reduction of the reactivity against human sera of buckwheat-allergy subjects, using immuno dot-blotting, QCM analysis and ELISA. In addition, the glycosylation of Fag e 1 yielded a great improvement of its surface functionality. Solubility of Fag e 1 at the neutral pH was substantially increased up to 13.5 times and 9.6 times by the conjugation with arabinogalactan and xyloglucan, respectively. Emulsifying properties of Fag e 1 were also improved by the glycosylation, of which both emulsifying activity and emulsion stability were more than 6 times higher than those of the native protein.  相似文献   
109.
Glass fibres for industrial use were laid on denture base materials such as self-curing and heat-curing resins to reinforce them. The use of heat-curing rather than self-curing resin as a base resin indicated a superior effect on bending properties.  相似文献   
110.
Sasaki  S. Kishimoto  T. Matsui  N. 《Electronics letters》1987,23(23):1238-1240
A new type of flip-chip interconnection technology usingstacked solder bumps is proposed, where the diameter of theupper solder bump is less than that of the lower ones. This isto reduce the capacitance between the stacked solder bumps and the ground plane and to prolong the lifetime ofthe solder joints.  相似文献   
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