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41.
Hydrogen and carbon dioxide adsorption with tetra‐n‐butyl ammonium semi‐clathrate hydrates for gas separations 下载免费PDF全文
Hiroyuki Komatsu Masaki Ota Yoshiyuki Sato Masaru Watanabe Richard L. Smith Jr. 《American Institute of Chemical Engineers》2015,61(3):992-1003
Gas adsorption rates of H2, CO2, and H2‐CO2 gas mixture (H2/CO2 = 3.4) with tetra‐n‐butyl ammonium salt (bromide, chloride, and fluoride) semi‐clathrate hydrate particles were measured at 269 K to assess their properties for gas separation. Equilibrium gas occupancies in the S‐cages of the particles were in order of (high to low) for hexagonal structure‐I, tetragonal structure‐I, and superlattice of cubic structure‐I structures with the maximum fractional occupancy by CO2 being about 40%. The CO2 diffusion rate depended on the anion size of the salt, which is attributed to distortion of the S‐cage that is close to the molecular size of CO2. Simulations of semi‐clathrate hydrate particles with theory showed that H2/CO2 selectivities could be as high as 36 (3.0 mol% TBAF) and that selectivities for an ideal membrane (3.3 mol% TBAF) could be >100 (269 K, 0.3–4.5 MPa). Semi‐clathrate hydrates have wide application as separation media for gas mixtures. © 2014 American Institute of Chemical Engineers AIChE J, 61: 992–1003, 2015 相似文献
42.
Corrosion characteristics of reduced activation ferritic steel, JLF-1 (8.92Cr–2W) in molten salts Flibe and Flinak 总被引:1,自引:0,他引:1
Masatoshi Kondo Takuya Nagasaka Qi Xu Takeo Muroga Akio Sagara Nobuaki Noda Daisuke Ninomiya Masaru Nagura Akihiro Suzuki Takayuki Terai Naoki Fujii 《Fusion Engineering and Design》2009,84(7-11):1081-1085
Static corrosion tests were performed in molten salts, LiF–BeF2 (Flibe) and LiF–NaF–KF (Flinak), at 500 °C and 600 °C for 1000 h. The purpose is to investigate the corrosion characteristics of reduced activation ferritic steels, JLF-1 (8.92Cr–2W) in the fluids. The concentration of hydrogen fluoride (HF) in the fluids was measured by slurry pH titration method before and after the exposure. The HF concentration determined the fluoridation potential. The corrosion was mainly caused by dissolution of Fe and Cr into the fluids due to fluoridation and/or electrochemical corrosion. Carbon on the surface might be dissolved into the fluids due to the corrosion, and this resulted to the decrease of carbide on the surface. The corrosion depth of the JLF-1 specimen, which was obtained from the weight losses, was 0.637 μm in Flibe at 600 °C and 6.73 μm in Flinak at 600 °C. 相似文献
43.
The authors propose a new design concept for controlling the deflection of a micro-membrane with the aid of its thickness distribution for realizing a prescribed design in the MEMS. As an example, the authors treat a micro air pump that comprises a micro-membrane. The membrane is actuated by an electrostatic force. The membrane deflects and thus the deflection is influenced by the air pressure and the electrostatic field. This is a highly complicated system. To find out a proper thickness distribution, the authors use the genetic algorithm that is appropriate to reduce the searching space of solution. 相似文献
44.
Masaru Nagura Akihiro Suzuki Takeo Muroga Takayuki Terai 《Fusion Engineering and Design》2009,84(7-11):1384-1387
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
45.
Masaru Ishii Mikihisa Saito Fumiyuki Fujii Michihiro Matsui Naoki Itamoto 《Electrical Engineering in Japan》2010,170(1):8-15
Lightning electric‐field waveforms related to power line faults in winter have been identified. Most of those waveforms appear to be associated with upward lightning discharges with absolute peak currents of over 100 kA. They are quite different from common return‐stroke waveforms, and the lightning discharges which produce these characteristic waveforms are called GC (Ground to Cloud) flashes. These high‐current lightning discharges are distributed around the coastline in different ways depending on their polarities. The spatial distributions of high‐current lightning discharges around Japan are also investigated. It is revealed that the region of Honshu Island along the coastline of the Sea of Japan belongs to the area in which the density of high‐current lightning flashes is the highest in Japan through the year. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 170(1): 8–15, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20874 相似文献
46.
Paule Njiwa Clotilde Minfray Thierry Le Mogne Béatrice Vacher Jean-Michel Martin Shigeki Matsui Masaru Mishina 《Tribology Letters》2011,44(1):19-30
In this study, we are interested in the anti-wear properties of zinc dialkyl phosphate additive (ZP) in comparison with ‘classical’ zinc dialkyldithiophosphate (ZDDP). Friction tests were performed on a reciprocating tribometer using both ball-on-flat and cylinder-on-flat configurations
under a Hertzian contact pressure of 0.9 GPa. Experiments were carried out as a function of temperature (25 and 100 °C), sliding
speed (25, 50 and 100 mm/s) and additives concentrations. Ball wear scar diameters as well as friction coefficient were measured.
In order to better understand the anti-wear mechanisms of these additives, friction tests were followed by surface analyses
such as AES (Auger Electron Spectroscopy) and XPS (X-Ray Photoelectron Spectroscopy). Transmission Electron Microscopy (TEM)
observations of the ZDDP and ZP tribofilms were also carried out to visualise the generated layers. The anti-wear capability of ZP molecule is discussed. 相似文献
47.
Electrical and dielectric behaviors and their origins in the three-dimensional polyvinyl alcohol/MWCNT composites with low percolation threshold 总被引:1,自引:0,他引:1
The electrical conductivity and dielectric behavior of a three-dimensional composite of polyvinyl alcohol (PVA) and multiwalled nanotubes (MWCNTs) were measured and an extremely low percolation threshold was observed. Two established theories were used to investigate the behaviors of the composites near the percolation threshold, and then the results indicated that the intercluster polarization effect is more reasonable to explain the electrical property of our system in the frequency range of measurement. The high value of the dielectric constant of the composites was attributed to interfacial polarization within the bulk sample and DC conductance based on charge injection at electrode-sample interface. Thus an equivalent circuit was established by separating the behavior of the bulk sample from that of the electrode-sample interface. The introduction of the concept of Constant Phase Element into the equivalent circuit model gave a fit in good agreement with the experimental data and implied the influence of a fractal interface on the real capacitance. The interfacial polarization and the relaxation processes were fully studied. As a result, the activation energy associated with those relaxation processes in the composites was thought to be the energy needed for the charges accumulating and bounded on the interfaces between MWCNT and PVA. 相似文献
48.
The literature concerning Schwann cells (SCs) and macrophages in myelin phagocytosis during Wallerian degeneration is reviewed. SCs carry out the first step in the removal of myelin by segmenting myelin and then incorporating the degraded myelin. The recruited macrophages then join in the myelin-phagocytosis event, appearing to make full use of their original phagocyte abilities until the end of myelin clearance. The molecular mechanisms of the two cells underlying myelin phagocytosis are thought to be different; myelin phagocytosis by SCs being lectin-mediated, i.e., opsonin-independent, whereas that of macrophages is mainly opsonin-dependent. It is important to note that SCs and macrophages cooperatively accomplish myelin phagocytosis. 相似文献
49.
Saitoh M Asaka K Arai M Kawabata A Kanoh S Kanoh T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2002,43(4):243-249
In order to evaluate the relationship between nasal carriers of S. aureus and their history of allergic diseases, the total serum IgE titer, the hemogramme pattern, and the titers of specific IgE antibody to Staphylococcal enterotoxins A and B (SEA and SEB) and of specific IgG antibody to SEB were investigated in 98 trade school students. Fifteen (15.3%) of the 98 students were sensitized to SEA and/or SEB (40.0% to SEA and 93.3% to SEB). In this group, 11 subjects were S. aureus carriers (73.0%) and 12 had a history of allergic diseases (80.0%). Low levels of specific IgG antibody to SEB were identified from both S. aureus carriers and non-carriers. The S. aureus carriers had significantly higher levels of total IgE titer than the non-carriers and the individuals with a history of allergic diseases had significantly higher total IgE titer levels than those having no history of allergic diseases (p < 0.01). In the hemogramme patterns of S. aureus carriers, a significant positive correlation was observed between the total IgE antibodies and the eosinophil rate (p < 0.05), and a negative correlation (p < 0.001) was recognized between the neutrophil and the lymphocyte rates. 相似文献
50.
Satoshi Hasegawa Kumi Sato Shohei Matsunuma Masaru Miyao Kohei Okamoto 《AI & Society》2005,19(3):265-278
A multilingual disaster information system (MLDI) has been developed to overcome the language barrier during times of natural disaster. MLDI is a web-based system that includes templates in nine languages so that translated texts can be made available immediately. Mobile phone e-mail with graphic text is a useful tool for delivering multilingual disaster information. The visibility of graphic text on mobile phones was measured and found to be equivalent to the built-in font. However, visibility deteriorates as the character size becomes smaller, especially, on displays with poor resolution. This article also discusses the necessity of multilingual information and measures for a safe and barrier-free society. 相似文献