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51.
Poly(styrene-co-acrylonitrile)/Cloisite 20A (95/5) nanocomposites, having various spatial dispersion levels of the clay, were prepared with controlling clay concentrations in a solvent by the coagulation method. X-ray diffraction, transmission electron microscopy and laser scanning confocal microscopy were used to characterize the structure and morphology of the nanocomposites on a nano-scale and on a micro-scale. Quantitative analysis of clay spatial dispersion in the nanocomposites based on the laser scanning confocal microscopy images was conducted from three different perspectives: 1) clay spatial distribution; 2) the non-clay-occupied domain size; and 3) the relationship between the frequency and intensity of pixels in the images. The results from these quantitative methods indicate that nanocomposites with different spatial dispersion levels of clay in the poly(styrene-co-acrylonitrile) matrix were obtained. Evidently, the ?d001 data from the X-ray diffraction was found to be not useful in measuring the clay dispersion in the nanocomposites. The effect of clay dispersion on the flammability properties of the nanocomposites and relevant mechanism of the clay dispersion having influence on flammability were also investigated. In radiant gasification experiments at 50 kW/m2, the best clay dispersion yielded a 32% reduction in peak mass loss rate, as compared to the nanocomposites with the worst dispersion. 相似文献
52.
Load-leveling hyper energy converting and utilization system (LHECUS) is a hybrid cycle which utilizes ammonia–water mixture as the working fluid in a combined power generation and refrigeration cycle. The power generation cycle functions as a Kalina cycle and an absorption refrigeration cycle is combined with it as a bottoming cycle. LHECUS is designed to utilize the waste heat from industry to produce cooling and power simultaneously. The refrigeration effect can be either transported to end-use sectors by means of a solution transportation absorption chiller (STA) as solution concentration difference or stored for demand load leveling. 相似文献
53.
N,O-type organic chelates reduced coordinated Cu2+ ions under hydrothermal reaction conditions to produce Cu2O/CuO nanoparticles. Chelates in which the N and O atoms are closely spaced produced smaller amounts of CuO nanoparticles, indicating their higher ability to reduce Cu2+ ions to Cu+ ions. [Cu(Gly)2]2 with the shortest ligand chain length produced only Cu2O nanoparticles and, therefore, can be used as a single molecule precursor for the synthesis of Cu2O nanoparticles. 相似文献
54.
Kinya Nakamura Masaki Kurata Takanari Ogata Takeshi Yokoo Michael A. Mignanelli 《Journal of Phase Equilibria and Diffusion》2001,22(3):259-264
An isothermal section of the Fe-Pu-U ternary system at 650 °C was assessed in a previous study. In the present study, the
predictions of the phase relations in the Fe-Pu-U system to higher and lower temperatures were performed by applying the interaction
parameters determined at 650 °C. Differential thermal analysis (DTA) for the Fe-Pu-U alloys was also carried out to confirm
the phase relations in the temperature region of 500 to 800 °C. Both results agreed well. On the basis of the predicted ternary
phase diagram, the phase relations for a region surrounded by Fe2Pu, Fe2U, U, and Pu were described by a reaction scheme and a projection of the liquidus surface. 相似文献
55.
Review of advanced absorption cycles: performance improvement and temperature lift enhancement 总被引:1,自引:0,他引:1
The objective of this study is to propose and evaluate advanced absorption cycles for the coefficient of performance (COP) improvement and temperature lift enhancement applications. The characteristics of each cycle are assessed from the viewpoints of the ideal cycle COP and its applications. The advanced cycles for the COP improvement are categorized according to their heat recovery method: condensation heat recovery, absorption heat recovery, and condensation/absorption heat recovery. In H2O–LiBr systems, the number of effects and the number of stages can be improved by adding a third or a fourth component to the solution pairs. The performance of NH3–H2O systems can be improved by internal heat recovery due to their thermal characteristics such as temperature gliding. NH3–H2O cycles can be combined with adsorption cycles and power generation cycles for waste heat utilization, performance improvement, panel heating and low temperature applications. The H2O–LiBr cycle is better from the high COP viewpoints for the evaporation temperature over 0°C while the NH3–H2O cycle is better from the viewpoint of low temperature applications. This study suggests that the cycle performance would be significantly improved by combining the advanced H2O–LiBr and NH3–H2O cycles. 相似文献
56.
Suzuki C.; Kawano M.; Kashiwagi T.; Arata Y.; Kawasumi T.; Kashiwagi Y. 《Protein engineering, design & selection : PEDS》2000,13(2):73-76
Expression of the SMK1 gene which encodes the yeast killer toxinSMKT is lethal in Saccharomyces cerevisiae. Effects of deletionand site-directed mutagenesis of SMK1 on the lethality and thesecretion of the gene products were examined. Deletion of theinterstitial 相似文献
57.
Ryuichi Shimokawa Michio Tajima Masatoshi Warashina Yusaku Kashiwagi Hitoshi Kawanami 《Solar Energy Materials & Solar Cells》1997,48(1-4)
We report the correspondence between the photoluminescence (PL) measurement, monochromatic-light-beam-induced current (MBIC) measurement and defect delineation in polycrystalline cast-Si solar cells. It was found that the peak of the band-edge PL emission in the hydrogenerated and non-hydrogenerated cast-Si shifted from 1.093 eV in the single crystalline CZ-Si to 1.075 eV at room temperature and the band-edge PL mapping corresponded with the MBIC mapping and defect delineation pattern if excluding the surface damages delineated by the MD-1 etchant. 相似文献
58.
N Koike T Todoroki T Kawamoto S Yoshida H Kashiwagi K Fukao T Ohno T Watanabe 《Canadian Metallurgical Quarterly》1998,13(6):1269-1274
The abilities of 9 kinds of human biliary tract carcinoma cell lines to invade through basement membrane or type I collagen were examined using an in vitro invasion assay system. The correlations between invasiveness and morphologic characteristics of the carcinoma cells in 3 dimensional collagen gel were also examined. most of the biliary tract carcinoma cell lines kept the abilities of glandular differentiation and basement membrane formation of the original tumor. Their invasiveness, however, correlated with the degree of in vitro morphologic differentiation regardless of their original morphology. 相似文献
59.
S Kashiwagi J Hayashi K Kakuda K Yamaji K Ueno Y Tani 《Canadian Metallurgical Quarterly》1995,69(3):297-302
A new immunochromatography assay (Dainascreen Ausab Dainabot) has been recently introduced for the detection of the presence of antibody to HBsAg. To evaluate the feasibility of using the Dainascreen Ausab, we carried out comparison tests with this method and PHA. In the test of 439 sera from HB vaccinees, inhabitants in Iki Island, Nagasaki Pref., patients with autoimmune diseases and with acute hepatitis B, 154 (31.2%) were positive by Dainascreen Ausab, 145 (29.4%) were positive by PHA and 145 (29.4%) were positive by both Dainascreen Ausab and PHA. Nine (1.8%) were positive by only Dainascreen and there were none positive by only PHA. A good correlation was observed between the titer of the antibody by this method and IMx. The anti-HBs assay by this method was able to be completed within 15 minutes and the procedure was very simple. The results indicate that the sensitivity of Dainascreen is superior to PHA and that it is easy to use. 相似文献
60.
The atrial natriuretic factor (ANF) induces diuresis, natriuresis, and vasodilation. Although it was originally found to be secreted from the atria, ANF synthesis has been demonstrated in other organs. The adult lung is not only the first target organ for ANF, but it also expresses the ANF gene and synthesizes, releases, and clears ANF from the circulation. We have shown the presence of ANF in human fetal lungs and also demonstrated that these lungs can release bioactive ANF. However, the role of the ANF system in the newborn lung is unknown. Therefore we studied the ANF system in pulmonary vessels (arteries and veins dissected from the hilum down to a 100-microm diameter), in isolated perfused lungs, and in the plasma from pulmonary artery and vein of 1- and 7-day-old piglets. High-performance liquid chromatography (HPLC) revealed the presence of both the mature peptide and the ANF prohormone in pulmonary vein microsomes, but in pulmonary arteries, only the mature form was identified. Furthermore, in the veins, the ANF content tended to be higher in 7- than in 1-day-olds. ANF caused a dose-dependent decrease in perfusion pressure (p < 0.05). In veins and arteries, most of the ANF receptors were of the type A guanylate cyclase as opposed to clearance receptors. Interestingly, the ANF receptors were fewer in veins, where synthesis takes place, than in arteries (p < 0.05). Significant circulating ANF plasma levels were measured by radioimmunoassay in both pulmonary artery and vein. However, there was no site difference in ANF plasma levels, suggesting that ANF is cleared and synthesized in the pulmonary vessels. In conclusion, the entire ANF system is present in the newborn piglet pulmonary vessels. The paucity of clearance receptors compared with functional receptors potentiates the role of ANF in the regulation of postnatal pulmonary vascular resistance. 相似文献