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41.
Shinji Kanehashi Yuko Tomita Hiroshi Kawakita Shuichi Sato Tetsuo Miyakoshi Kazukiyo Nagai 《应用聚合物科学杂志》2013,129(4):2036-2045
Poly[methacryloxypropylheptacyclopentyl‐T8‐silsesquioxane (MAPOSS)‐co‐3‐methacryloxypropyltris(trimethylsiloxy)silane (SiMA)] was synthesized through free radical polymerization. The physical and carbon dioxide (CO2) sorption properties of the copolymer membranes were investigated in terms of the MAPOSS content. As the MAPOSS content increases, the membrane density increased, suggesting a decrease in the fractional free volume. In addition, the thermal stability was improved with increasing the MAPOSS content. These are because of the polyhedraloligomericilsesquioxane (POSS) units that restrict the high mobility of poly(SiMA) segments. The glass transition temperature, Tg of the copolymers was single Tg based on the differential scanning calorimetry, suggesting that the copolymers were random and not phase separation. Based on the CO2 sorption measurement, the POSS units play a role in reducing Henry's dissolution by suppressing the mobility of the poly(SiMA) component, while POSS units increase the nonequilibrium excess free volume, which contributes to the Langmuir dissolution. Based on these results, the introduction of MAPOSS unit is one of the effective ways to improved the thermal stability and CO2 sorption property due to the enhancement of the polymer rigidity. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
42.
Chand R Narimura K Kawakita H Ohto K Watari T Inoue K 《Journal of hazardous materials》2009,163(1):245-250
Grape waste generated in wine production is a cellulosic material rich in polyphenolic compounds which exhibits a high affinity for heavy metal ions. An adsorption gel was prepared from grape waste by cross-linking with concentrated sulfuric acid. It was characterized and utilized for the removal of Cr(VI) from synthetic aqueous solution. Adsorption tests were conducted in batch mode to study the effects of pH, contact time and adsorption isotherm of Cr(VI), which followed the Langmuir type adsorption and exhibited a maximum loading capacity of 1.91 mol/kg at pH 4. The adsorption of different metal ions like Cr(VI), Cr(III), Fe(III), Zn(II), Cd(II) and Pb(II) from aqueous solution at different pH values 1-5 has also been investigated. The cross-linked grape waste gel was found to selectively adsorb Cr(VI) over other metal ions tested. The results suggest that cross-linked grape waste gel has high possibility to be used as effective adsorbent for Cr(VI) removal. 相似文献
43.
Jin Kawakita Tadashi Shinohara Seiji Kuroda Masato Suzuki Satoshi Sodeoka 《Surface & coatings technology》2008,202(16):4028-4035
Titanium dioxide TiO2 can be used as a photo-anode to give generated electrons to the metal substrate under illumination. The transition metal oxide such as iron oxide Fe2O3 can be used to store electrons generated by the photo-electric conversion function of TiO2 under the illuminated situation while the electrons are discharged from the transition metal oxide to the metal substrate in the dark. In this paper, coatings of nano-sized composite of TiO2 and Fe2O3 were fabricated by the Warm Spray process, in which the feedstock powder is accelerated by a supersonic gas jet with speed above 1.0 km s- 1 and temperature between 800 and 2500 K, and then impacted onto the target substrate continuously to form coatings. The coatings of TiO2 and Fe2O3 nano-composite fabricated by Warm Spray showed no thermal deterioration such as phase transformation and particle growth of the feedstock during the spray process. The coatings fabricated by the Warm Spray had larger photo-current and the electron charge/discharge capacity than that by a conventional HVOF process. In addition, these characteristics were improved by decreasing the primary particle size of TiO2 and Fe2O3. 相似文献
44.
Previous somatic cell hybridization studies have assigned many human cell lines to one of four complementation groups (A-D) for immortalization. We report here that the A1698DM cell line, which contains selectable markers and has previously been defined as the immortalization group D representative, was derived from T24 cells rather than A1698. A1698DM did not undergo senescence when fused with cell lines assigned to groups A, B, or C. This raises the possibility that this cell line has undergone further evolution and lost multiple putative senescence genes so that it is now unable to complement any, or most, other cell lines for senescence. Cell lines previously assigned to group D may, therefore, be heterogeneous with respect to the genetic changes that resulted in their immortalization. This has important implications for strategies to clone senescence genes based on complementation groups. 相似文献
45.
Yoshiaki Tsunawaki Nobuhisa Ohigashi Kunioki Mima Shin-ichiro Kurama Kazuo Imasaki Masayuki Fujita Chiyoe Yamanaka Sadao Nakai 《Journal of Infrared, Millimeter and Terahertz Waves》1995,16(1):317-325
A three dimensional simulation software system developed to estimate a free electron laser (FEL) gain has been applied to FEL using a standard plane polarized wiggler and an alternately shifted magnet wiggler. It is seen for the latter wiggler that a large filling factor could be selected and each maximum gain corresponding to each orbit of electron beam concentrates at a certain frequency region of FEL radiation. It is, therefore, implied that a proper shift between the adjacent magnets in the wiggler produces the improvement of the FEL gain. 相似文献
46.
Yuichi Nakazato Akiyoshi Sekine Hajime Miyazawa Sadao Takeuchi Yukinori Ariga Masao Murakawa 《Microsystem Technologies》2005,11(8-10):997-1004
In this study we focus on diamond as a structural material for micromechanisms. Diamond is the hardest material on the earth, and has superior antifriction and anticorrosion characteristics. If diamond were applied to a micromechanism, an almost maintenance-free component which requires only a few component exchanges could be fabricated. In addition, since it has a superior anticorrosion characteristic, it can be used in chemical substances and organic tissue; thus, micromechanical components made of diamond have many advantages. Furthermore, when diamond is applied to a micromanipulator, we can expect accurate gripping to be realized because its deformation is small. We have already developed a diamond end effector for micromanipulators, and have obtained several promising results. In this study, we added a reversal mechanism to the positioning unit of this micromanipulator to increase efficiency in assembly tasks, and modified the design of the diamond end effector accordingly. Major modifications were examined through finite element analysis of fabricated shapes and amount of movement. A modified effector was experimentally fabricated based on the analytical results, and its features were examined experimentally. The starting material was 2-μm-thick flat-plate diamond, whichwas processed by laser into a designated shape. A shape-memory-alloy actuator which memorizes the linear shape was used to realize a driving amount larger than those of electrostatic actuators and piezoelectric devices. 相似文献
47.
S Kawakita 《Canadian Metallurgical Quarterly》1996,44(9):899-902
A 73-year-old male, who underwent resection of soft palate cancer and was under treatment for esophageal ulcer at our medical department, complained of palpitation. On the suspicion of hyperthyroidism, enzyme immunoassay (EIA) was performed. T3 and T4 were increased, and FT4 and TSH were normal. However, T3 and T4 measured again by radioimmunoassay (RIA) were normal. Therefore, the patient serum was examined for interfering substances such as antibody against bovine intestinal alkaline phosphatase (ALP) and heterophilic antibody. Substances interfering with ALP and anti-rabbit IgG human antibody were detected. It is necessary to consider the possible presence of these substances when results of EIA are evaluated. 相似文献
48.
K Hiramatsu M Sugimoto S Kamei M Hoshino K Kinoshita K Iwasaki M Kawakita 《Canadian Metallurgical Quarterly》1997,123(10):539-545
Recently, we found N1,N8-diacetylspermidine (Ac2Spd) and N1,N12-diacetylspermine (Ac2Spm) in human urine, and noted that their amount increased significantly in patients with urogenital malignancies. Previous findings that simultaneous reference to these diacetylpolyamines is useful in distinguishing cancer patients from healthy persons were confirmed by more recent analytical data on urine samples from several cancer patients. Further examination revealed that urinary Ac2Spm and Ac2Spd tended to decrease when cancer patients were treated and entered partial remission. In cases where the Ac2Spm and Ac2Spd levels were normal or near-normal after treatments, the prognosis of the patients was generally good. In contrast, when their level remained far above the normal limits after apparently effective treatment, the prognosis of the patients was poor. When a patient is in remission for more than 3 years, urinary levels of both Ac2Spm and Ac2Spd are stabilized and stay below the normal limits, with rare exceptions. The recurrence of a cancer as well as the complication of a second one during the period of follow-up examination was accompanied by elevation of urinary diacetylpolyamines. These observations indicate that urinary Ac2Spm and Ac2Spd are useful as prognostic indicators after treatment and during follow-up examination of cancer patients. 相似文献
49.
High temperature corrosion of nanoceria coated 9Cr-1Mo ferritic steel in air and steam 总被引:1,自引:0,他引:1
In this article, air and steam oxidation resistance of bare and nanoceria coated 9Cr-1Mo ferritic steel at 650 °C for 500 h is reported. The kinetics of the oxidation process and the changes in the morphology and the chemistry for both the specimens were analyzed by backscattered electron and EPMA mapping. The nanoceria coated 9Cr-1Mo ferritic steel showed better oxidation resistance than uncoated steel under similar conditions. The thickness of the oxide scales formed on the coated samples was significantly reduced as compared to the uncoated substrates. The effectiveness of such a thin and simple nanocoating to improve the oxidation resistance of 9Cr-1Mo ferritic steel compared to the pristine is attributed to the change in the migration of cations from outward to inward diffusion of oxygen as the major mechanism. 相似文献
50.
Yoshimasa Murayama Sadao Nakajima 《Journal of Superconductivity and Novel Magnetism》1994,7(6):909-912
A doublon formalism ofd-p model Hubbard Hamiltonian is studied only with transfer integrals, and without the superexchange term. This gives excellent doping-dependent features ofT c in high-T c cuprates. 相似文献