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91.
Obuchi Akira Uchisawa Junko Ohi Akihiko Nanba Tetsuya Nakayama Norio 《Topics in Catalysis》2007,42(1-4):267-271
Based on a folded sheet design, we made and tested a miniature diesel particulate filter (DPF) that can transfer the heat
generated by catalytic oxidation in the DPF to its upstream, thus promoting substantial temperature rise at the position where
pieces of SiC felt working as PM filters are situated. When 0.6% of H2, corresponding to 50 K in adiabatic temperature rise, was added to a 43 L/min of exhaust gas, the observed maximum temperature
rise at the filter material exceeded 350 K, from which the heat recovery rate was estimated to be more than 86%. The PM filtration
rates were 80–90%. 相似文献
92.
Kiyoko Sakamoto Shunro Yamaguchi Atsushi Nakahira Motoki Kaneno Masayuki Okazaki Junko Ichihara Yoshiaki Tsunawaki James C. Elliott 《Journal of Materials Science》2002,37(5):1033-1041
Hydrolyses of -tricalcium bis(orthophosphate) Ca3(PO4)2 (-TCP) were carried out in a heterogeneous solvent system (hydrophobic organic solvent-water). The hydroxyapatites (HAp) formed were deficient in calcium (Ca/P = 1.56–1.61, a-axis = 0.9440 nm, c-axis = 0.6880 nm) and contained acid phosphate (and sometimes carbonate depending on the organic solvent used). The HAp was in the form of needles with a length (1–4 m) that depended on the polarity of the hydrophobic organic solvent. The aspect ratio was highest in 1-octanol with a polarity of E
T = 48.3. On the other hand, in a hydrophobic organic solvent system without OH groups such as n-octane (E
T = 31.1), HAp formed fine particles that are similar to HAp prepared in a system without an organic solvent. Thus, hydrophobicity and OH groups of organic solvents affect the crystal growth of HAp. 相似文献
93.
Daniel E. Meeroff Thomas D. Waite Junko Kazumi Charles N. Kurucz 《Canadian Metallurgical Quarterly》2004,130(2):155-166
Laboratory and pilot tests were conducted to investigate the use of ionizing radiation at an activated sludge wastewater treatment facility with residuals processing. Operational enhancements were investigated with respect to bulking control, thickening enhancement, and anaerobic stabilization processes. Radiation caused permanent effects in measured sludge parameters including solids content, chemical oxygen demand, ammonia-nitrogen, zeta potential, specific surface area, resistance to filtration, sludge volume index, pH, organic acid production, and digester gas evolution. Analysis of beneficial effects from preliminary studies and pilot tests demonstrated that a dose of 2–3 kGy would be potentially successful for bulking control and to a lesser degree, enhanced thickening and radiation-assisted anaerobic digestion. A cost analysis based on preliminary tests determined that a centralized electron beam irradiator could be applied economically in an integrated approach at an estimated annual savings of $0.2–2.7 million depending upon the application. Considering that the annual cost of operating an accelerator unit was estimated at $2.4 million ($2.16/m3), this might translate into an important savings for a large-scale wastewater treatment facility. 相似文献
94.
Catalysis of decomposition of dilute N, N'-dimethylformamide was explored. Among the catalysts investigated, Pt displayed the highest activity at low temperatures (~200 °C) and DMF conversion was promoted by H2 addition to the feed. As the Pt support material, H-ZSM-5 exhibited the best performance at around 200 °C in terms of harmless decomposition. 相似文献
95.
The thermally stimulated current (TSC) technique has been used to investigate molecular relaxation in poly(ethylene terephthalate) (PET) films unstretched and biaxially stretched at 90 and 95 °C. Unstretched PET films show two peaks at 77 and 90 °C corresponding to α and ρ relaxation processes, respectively. The α relaxation is associated with the main glass transition of the material. The ρ peak with lower intensity is attributable to permanent dipoles. Both biaxially stretched samples show one TSC peak at 95 °C, supposed to correspond to ρ relaxation. The disappearance of the α peak, accompanied by the displacement of the ρ peak to higher temperature, is the result of the higher thermal stability of the permanent dipoles, which is strongly influenced by the stiffening of amorphous parts and the crystallization by stretching. In both stretched samples, the continuous distribution of pre-exponential factors over activation energies observed might correspond to a single relaxation mode. The kinematics of stretching PET has been discussed in terms of activation energy and temperature dependence of relaxation time. © 1999 Society of Chemical Industry 相似文献
96.
Mayuko Ikarashi Junko Tsuchida Masayuki Nagahashi Shiho Takeuchi Kazuki Moro Chie Toshikawa Shun Abe Hiroshi Ichikawa Yoshifumi Shimada Jun Sakata Yu Koyama Nobuaki Sato Nitai C. Hait Yiwei Ling Shujiro Okuda Kazuaki Takabe Toshifumi Wakai 《International journal of molecular sciences》2021,22(24)
Although numerous experiments revealed an essential role of a lipid mediator, sphingosine-1-phosphate (S1P), in breast cancer (BC) progression, the clinical significance of S1P remains unclear due to the difficulty of measuring lipids in patients. The aim of this study was to determine the plasma concentration of S1P in estrogen receptor (ER)-positive BC patients, as well as to investigate its clinical significance. We further explored the possibility of a treatment strategy targeting S1P in ER-positive BC patients by examining the effect of FTY720, a functional antagonist of S1P receptors, on hormone therapy-resistant cells. Plasma S1P levels were significantly higher in patients negative for progesterone receptor (PgR) expression than in those positive for expression (p = 0.003). Plasma S1P levels were also significantly higher in patients with larger tumor size (p = 0.012), lymph node metastasis (p = 0.014), and advanced cancer stage (p = 0.003), suggesting that higher levels of plasma S1P are associated with cancer progression. FTY720 suppressed the viability of not only wildtype MCF-7 cells, but also hormone therapy-resistant MCF-7 cells. Targeting S1P signaling in ER-positive BC appears to be a possible new treatment strategy, even for hormone therapy-resistant patients. 相似文献
97.
Kenji Takumi Junko Udaka Makoto Kanoh Tetsuro Koga Hideaki Tsuji 《Journal of the science of food and agriculture》1996,72(2):141-147
Prolamins from Italian, common and Japanese millet cultivars were separately extracted with three kinds of alcohol (ethanol, propanol and isopropanol) and their component polypeptides and immunochemical relationships were examined by SDS-PAGE, two-dimensional electrophoresis and immunoblot analysis using the antiserum raised against Italian millet prolamin. Polypeptides of the individual millet prolamins appeared to be primarily composed of two major common subunit complexes with respective molecular masses ranging from about 19 to 23 kDa and from 13 to 14 kDa (groups A and B, respectively), although a few minor variations due to varietal differences were seen. Group A clearly contained one neutral subunit (21 kDa) and one basic one (22 kDa), while group B had one basic 14 kDa subunit. The Italian millet prolamin antiserum strongly bound with all three prolamin polypeptides but neither with the homologous non-prolamin fractions nor with the heterogeneous prolamins of the Triticeae (wheat, barley and rye). Amino acid compositions were found to be almost identical to one another. 相似文献
98.
Role of lanthanide elements on the catalytic behavior of supported Pd catalysts in the reduction of NO with methane 总被引:2,自引:0,他引:2
In this study, the role of lanthanide elements (Ce, Gd, La, and Yb) on Pd/TiO2 catalysts in the catalytic reduction of NO with methane was investigated. Steady-state reaction experiments in the presence of oxygen showed that the addition of lanthanide elements increases the oxygen resistance of the catalyst. The post-reaction XPS characterization results revealed that majority of the Pd sites remained in the zero oxidation state in the presence of Ce or Gd. The effect of SO2 (145 ppm) and H2O (0–6.6%) in NO–CH4–O2 reaction over supported Pd and Gd–Pd catalysts was also investigated. Over the Gd–Pd catalyst with the presence of SO2, more than 70% NO conversion was obtained for over 6 h while the Pd only catalyst showed a sharper drop in NO conversion. Over the Gd–Pd catalyst, the presence of H2O showed no effect on NO conversion activity (>99% conversion) during the 18 h the catalyst was kept on stream. Among the lanthanide elements tested, Gd is the most effective, allowing the use of above stoichiometric oxygen concentration. 相似文献
99.
Hiroshi Abe Ryunosuke Note Hiroshi Mizuseki Yoshiyuki Kawazoe Junko Habasaki Ikuyoshi Tomita 《Journal of Inorganic and Organometallic Polymers and Materials》2012,22(4):845-851
In order to simulate the thermal behavior of one of the most useful inorganic–organic hybrid materials, octa-functional polyhedral oligomeric silsesquioxane (POSS), molecular dynamics (MD) simulations of crystals of POSSs having methyl, i-butyl, and cyclopentyl substituents were performed using the universal force field. The crystal structures obtained by the MD calculations were in good agreement with those reported based on experimental results. On the basis of their molecular expansion behaviors, the lattice lengths were also evaluated, from which the expansion of each lattice length as a function of temperature was found to be dependent upon the substituents. 相似文献
100.
Hiromi Yamashita Masaru Harada Junko Misaka Masato Takeuchi Bernaurdshaw Neppolian Masakazu Anpo 《Catalysis Today》2003,84(3-4):191-196
The application of metal ion-implantation method has been made to improve the electronic properties of the TiO2 photocatalyst to realize the utilization of visible light. The photocatalytic properties of these unique TiO2 photocatalysts for the purification of water have been investigated. By the metal ion-implantation method, metal ions (Fe+, Mn+, V+, etc.) are accelerated enough to have the high kinetic energy (150 keV) and can be implanted into the bulk of TiO2. TiO2 photocatalysts which can absorb visible light and work as a photocatalyst efficiently under visible light irradiation were successfully prepared using this advanced technique. The UV-Vis absorption spectra of these metal ion-implanted TiO2 photocatalysts were found to shift toward visible light regions depending on the amount and the kind of metal ions implanted. They were found to exhibit an effective photocatalytic reactivity for the liquid-phase degradation of 2-propanol diluted in water at 295 K under visible light (λ>450 nm) irradiation. The investigation using XAFS analysis suggested that the substitution of Ti ions in TiO2 lattice with implanted metal ions is important to modify TiO2 to be able to adsorb visible light. 相似文献