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51.
Carbon-coated W18O49 powders were prepared from the mixture of para-ammonium tungstate with poly(vinyl alcohol) by heat treatment in inert atmosphere at a temperature between 750 and 900 °C for 1 h. The synthesized W18O49 crystals had prismatic morphology in small size, less than 0.5 μm in diameter and about 1 μm in length. Carbon-coated W18O49 was shown to have photoactivity under visible light irradiation by comparing the concentration changes of methylene blue, phenol and dimethylsulfoxide with time under the irradiation of visible light to that in the dark. Photoactivity of W18O49 was supposed to be due to the formation of OH radicals on the basis of the degradation of dimethylsulfoxide, its quantitative transformation to methanesulfonic acid. Carbon coating seemed to have various roles: to reduce WO3 to W18O49, to inhibit the sintering and crystal growth of W18O49 to keep them small size, and also to concentrate pollutants around W18O49 crystal by adsorption.  相似文献   
52.
A 64-tap FIR (finite impulse response) digital filter that has been designed using a newly developed filter compiler and fabricated in a 0.8-μm triple-level interconnect BiCMOS gate array technology is presented. The filter has been tested and is fully functional at a 100-MHz clock rate. These results are obtained by combining an optimized architecture and gate array floorplan with submicrometer BiCMOS technology. The filter occupies 49 mm2, which is approximately two-thirds of the 100 K gate array core. The design uses an equivalent of 55 K gates (two-input NAND gates). The device input/output are 100 K emitter-coupled-logic (ECL) compatible  相似文献   
53.
Four-week-old male Sprague-Dawley rats underwent a 90% small bowel resection. From the fourth day after surgery, they were divided into group 1 and 2, and pair-fed by elemental diets (0.8 kcal/mL, 50 mL/day) with L-arginine (n = 10) or L-glycine (n = 11) as an isonitrogenous and isoenergetic supplement for 3 weeks. They were compared with each other 3 weeks after surgery. A statistical analysis was performed using the unpaired Student's t test and the one-way factorial analysis of variance (ANOVA) using Bonferroni/Dunn multiple comparison test. A Pvalue of < .05 was considered significant. There were no significant differences between the two groups in food intake, body weight, tail length, residual ileal length, and plasma IGF-I level. However, the mean height of ileal villi in group 1 showed higher than that in group 2 (P < .01). Growth hormone-releasing hormone (GHRH) provocative tests (1 microg per rat, intravenously) showed the more significant elevation of growth hormone IGH) secretion in the arginine supplement group than that of glycine supplement group at 5 minutes (P < .05). There were no significant differences between basal levels of plasma rat GH in both groups. It is suggested that arginine has a possible significant role of GH secretion and intestinal mucosal growth after massive small bowel resection.  相似文献   
54.
Electroluminescent (EL) diodes utilizing metal-free phthalocyanine (H2Pc) have been fabricated by the vacuum evaporation method. The EL characteristics of the diodes depending upon the metal cathode and the characteristics of the diodes with the coevaporated layer with 4-(dicyanomethylene)-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran (DCM) have been investigated. We have demonstrated the infrared electroluminescence originated from the radiative transition corresponding to the Q band of H2Pc by taking the energy band structure into consideration  相似文献   
55.
A composite material of amorphous calcium carbonate and aspartic acid (Asp) was synthesized using a highly concentrated solution of calcium aspartate: a new approach. A transparent and amorphous solid with approximately 1 mm thickness was obtained. UV-vis transmittance spectrum of the composite shows no characteristic absorption in visible region. A Raman spectrum of the composite revealed a peak assigned to the symmetric stretching of carbonate ion. This study demonstrated that amorphous calcium carbonate could be stabilized using not only organic artificial macromolecules but also using Asp, a small biomolecule. This result is expected to engender development of new biomimetic materials.  相似文献   
56.
Here, we report the fabrication of a chemical gradient microfluidic device for single-cell cytotoxicity assays. This device consists of a microfluidic chemical gradient generator and a microcavity array that enables entrapment of cells with high efficiency at 88 ± 6% of the loaded cells. A 2-fold logarithmic chemical gradient generator that is capable of generating a serial 2-fold gradient was designed and then integrated with the microcavity array. High density single-cell entrapment was demonstrated in the device without cell damage, which was performed in 30 s. Finally, we validated the feasibility of this device to perform cytotoxicity assays by exposing cells to potassium cyanide (0-100 μM KCN). The device captured images of 4000 single cells affected by 6 concentrations of KCN and determined cell viability by counting the effected cells. Image scanning of the microcavity array was completed within 10 min using a 10× objective lens and a motorized stage. Aligning cells on the microcavity array eases cell counting, observation, imaging, and evaluation of singular cells. Thus, this platform was able to determine the cytotoxicity of chemicals at a single-cell level, as well as trace the cytotoxicity over time. This device and method will be useful for cytotoxicity analysis and basic biomedical research.  相似文献   
57.
Colloid particles have superlong-range attractive and repulsive forces. The distance between the secondary minimum of the potential energy of the interaction and the surface of the colloid is of the order of several μm and several tens of μm. These interactions clearly appear in the distribution of order-solution phase coexistence, in gathering particles to the ordered phase and in spontaneous pair formation. A new ‘Dynamic electrical multipole model and resonance effect’ is given. From this model, it is predicted that pairs will form in a shear field even in highly concentrated salt solution. Pair formation was observed after 24 hours as predicted.  相似文献   
58.
Yoshino  Ryozo 《Behaviormetrika》1989,16(25):49-63

The concept of stability has been developed in structural stabilty theory of mathematics. This concept plays an important role in characterizing the nature of a scientific law. Yoshino (1989a) introduced it into axiomatic measurement theory developed by mathematical psychologists, and analyzed some experimental data concerning psychophysical laws. The main objective of the present paper is to develop a concept of “degree of stability” for the further study of the nature of a scientific law, especially, a psychophysical law. Some experimental data on the Stevens’ power law arc analyzed from the standpoint of degree of stability. Finally, some possible experiments are suggested for the future development of this research.

  相似文献   
59.
The cells of origin of peripheral nerves that supply the temporomandibular joint were investigated by examining the centripetal transport of wheat germ agglutinin-horseradish peroxidase (WGA-HRP). Following WGA-HRP injection into the temporomandibular joint capsule of the cat, a large number of labelled neurones were observed in the trigeminal and superior cervical ganglia ipsilateral to the injection site, while no labelled neurones were detected in the cervical dorsal-root ganglia. Only one labelled neurone was seen in the stellate ganglion. Labelled neurones were primarily located in the posterolateral and dorsal regions of the trigeminal ganglion, but their distribution in the superior cervical ganglion was not localized to specific regions. The labelled neurones in the trigeminal ganglion were significantly larger than those in the superior cervical ganglion but the sizes of smaller neurones overlapped, suggesting that trigeminal ganglion neurones send both myelinated and unmyelinated fibres to the temporomandibular joint. The innervation of the temporomandibular joint by somatosensory and sympathetic fibres suggests that sympathetic nerves could be responsible for allodynia or neuropathic pain caused by temporomandibular disorders.  相似文献   
60.
Zheng  Yuejun  Yoshino  Ryozo 《Behaviormetrika》2003,30(1):21-37

This paper analyzes the longitudinal changes of Japanese attitudes toward nature and environment (ATNE) using Japanese character survey data, and explores the structural characteristics of response patterns to the ATNE in Japan, USA and five European nations based on analytical results derived from crossnational survey data. We also discuss the relationships of respondent’s attributes relative to the structure of their response patterns using the visual configuration obtained by correspondence analysis. In addition, we verify how racial, cultural, geographic diversities change people’s ATNE in various circumstances. As a result, we have found that Japan is similar to France, and Germany is similar to Britain and the Netherlands. We have also seen that the USA is similar to Italy in the aspect of the ATNE whereas the Japanese have their own distinctive structures of response patterns to the ATNE when compared to the Americans and the Europeans.

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