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91.
Four new diimide-dicarboxylic acids (I–IV) were prepared by condensation of s- or a-BPDA with para- or meta-aminobenzoic acid. A series of aromatic poly(amide-imide)s containing these diimide-dicarboxylic units was prepared by three methods: (1) acid chloride method, (2) triphenylphosphite method, and (3) one-pot method. A typical polymer of the series is readily soluble in polar aprotic solvents such as N-methyl-2-pyrrolidone (NMP), dimethylsulfoxide (DMSO), and pyridine (py) and could be cast into tough and flexible films. These were characterized by inherent viscosity, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) measurements. The glass transition temperatures of these polymers were in the range of 220–290°C, and the 5% weight loss temperatures were 450–500°C. Films prepared by casting from polymer solutions exhibited good tensile properties. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 63: 865–873, 1997 相似文献
92.
We have proposed a Tripolar Electrode Stimulation Method (TESM) which may succeed in narrowing the stimulation region and continuously moving the stimulation site for cochlear implants. The TESM stimulates the auditory nerve array through lymphatic fluid by means of three adjacent electrodes selected from among an electrode array. Currents are emitted from the electrodes on each side and the central electrode receives them. The current received by the latter electrode is equal to the sum of the currents emitted from the electrodes on the two sides. In this paper, the electric intensity profiles produced by the TESM and by monopolar stimulation were measured in a human cadaver cochlea and in a saline solution. We found that in the TESM, the electric intensity profile produced in the human cadaver cochlea was about the same as that in the saline solution. In addition, in the TESM, the electric intensity profile was much sharper than that of monopolar stimulation in the human cadaver cochlea. Furthermore, the nervous excitation region could be localized in a certain range by means of TESM. © 1999 Scripta Technica, Electr Eng Jpn, 129(1): 1–9, 1999 相似文献
93.
Lithium phosphorus oxynitride (LiPON) films were prepared by radio frequency magnetron sputtering. In order to control the atomic composition of the films, a mixture of Li3PO4 and Li2O powders was used as the sputtering target. The ionic conductivity of the films showed a maximum (6.4 × 10− 6 S/cm) when the molar ratio of Li3PO4 to Li2O in the target was 1:2. The films formed from a target not containing Li2O showed good durability in air at the expense of slightly poorer ionic conductivity. This is probably due to the amount of Li in the film being significantly less which effectively suppressed absorption of CO2 in air. 相似文献
94.
95.
Gentoku Kido Mikihiro Takasaki Kimitaka Minami Hisashi Tanaka Hiroshi Ogawa Tohru Kawamoto 《Journal of Nuclear Science and Technology》2017,54(11):1157-1162
Ash-washing technology is a crucially important technology for removing radioactive Cs from contaminated ash. For that technology, Cs+ removal from the ash-washing solution by the adsorbent is necessary. This study was conducted to establish rapid preparation of appropriate adsorption columns for Cs+ uptake. A one-site model was not used for analysis because the model cannot accommodate sites with different adsorption speed. Results demonstrated that the adsorption behavior of the column filled with the granules of potassium copper hexacyanoferrate was well reproduced by a two-site adsorption model with parameters chosen through analysis of batch adsorption test results. 相似文献
96.
M-substituted Ca(Cu3−xMx)Ti4O12 (CCMTO) ceramics, where M = Fe and Ni, were synthesized and the influence of M substitutions for Cu on the crystal structure and ferroelectric properties of CCMTO ceramics were investigated in this study. From the variations in the lattice parameters of CCMTO ceramics, the solubility limit of Ni substitution for Cu in CaCu3−xNixTi4O12 (CCNTO) ceramics was x = 0.2, whereas that of CaCu3−xFexTi4O12 (CCFTO) ceramics was x = 0.05. The crystal structural analysis of CCMTO ceramics revealed that the single phase of CCMTO ceramics belongs to the I23 non-centrosymmetric space group of I23; as a result, the Pr and Ec values of CCFTO ceramics at x = 0.05 were 1.8 μC/cm2 and 40 kV/cm, respectively. The ferroelectric behavior of CCMTO ceramics by the M substitutions for Cu may be related to the displacement of a Ti4+ cation in the TiO6 octahedra and tilting of the Ti–O–Ti angle because of the non-centrosymmetric space group. 相似文献
97.
Akira Kariyasaki Yoshikazu Yamasaki Masazumi Kagawa Tohru Nagashima Akiharu Ousaka Shigeharu Morooka 《传热工程》2013,34(1-2):28-36
A technique was developed and tested to measure the local thickness of a droplet or a liquid film on a surface of an opaque or thick single transparent plate by an interference fringe pattern that was easily formed by reflecting laser lights. Monochromatic epi-illumination through an objective lens of a conventional microscope was provided by a 5 mW or 300 mW laser and a filter to remove the noise caused by laser speckle. The incremental height difference of the liquid layer between neighboring maxima or minima of fringes was evaluated from the wavelength of the laser light and the refractive index of the liquid. Estimation error of a local inclination angle was discussed using ray tracing under parallel illumination approximation. Droplet profiles evaluated from the interferogram that were obtained by the present fringe method agreed well with those by Laser Focus Displacement Meter. Measurement was made to ensure the usefulness of the present technique. It was made clear that the contact angle of a liquid droplet could be obtained precisely and swiftly, even in small size or small contact angle, and that instantaneous three-dimensional profile of a liquid film on a bubble moving in a microchannel could be measured. The fringe method had sufficient potential to obtain more detailed information about three-dimensional characteristics of liquid film in flows such as the generation, breakdown, and growth of waves and the liquid film on a bubble at the beginning of movement. 相似文献
98.
Noike M Liu C Ono Y Hamano Y Toyomasu T Sassa T Kato N Dairi T 《Chembiochem : a European journal of chemical biology》2012,13(4):566-573
Isoprenoids form the largest family of compounds found in nature. Isoprenoids are often attached to other moieties such as aromatic compounds, indoles/tryptophan, and flavonoids. These reactions are catalyzed by three phylogenetically distinct prenyltransferases: soluble aromatic prenyltransferases identified mainly in actinobacteria, soluble indole prenyltransferases mostly in fungi, and membrane‐bound prenyltransferases in various organisms. Fusicoccin A (FC A) is a diterpene glycoside produced by the plant‐pathogenic fungus Phomopsis amygdali and has a unique O‐prenylated glucose moiety. In this study, we identified for the first time, from a genome database of P. amygdali, a gene (papt) encoding a prenyltransferase that reversibly transfers dimethylallyl diphosphate (DMAPP) to the 6′‐hydroxy group of the glucose moiety of FC A to yield an O‐prenylated sugar. An in vitro assay with a recombinant enzyme was also developed. Detailed analyses with recombinant PAPT showed that the enzyme is likely to be a monomer and requires no divalent cations. The optimum pH and temperature were 8.0 and 50 °C, respectively. Km values were calculated as 0.49±0.037 μM for FC P (a plausible intermediate of FC A biosynthesis) and 8.3±0.63 μM for DMAPP, with a kcat of 55.3±3.3×10?3 s. The enzyme did not act on representative substrates of the above‐mentioned three types of prenyltransferase, but showed a weak transfer activity of geranyl diphosphate to FC P. 相似文献
99.
Koya Arai Masanori Matsubara Yukie Sawada Tatsuya Sakamoto Tohru Kineri Yasuo Kogo Tsutomu Iida Keishi Nishio 《Journal of Electronic Materials》2012,41(6):1771-1777
A single ??-structure thermoelectric (TE) module based on p-type NaCo2O4, n-type Mg2Si, and Ni electrode was fabricated by the spark plasma sintering (SPS) method. The NaCo2O4 powder was synthesized by using a metal?Ccitric acid complex decomposition method. Bulk Mg2Si prepared by melt quenching was ground into a powder and sieved to particle size of 75???m or less. To obtain a sintered body of NaCo2O4 or Mg2Si, the powder was sintered using SPS. Pressed Ni powder or mixed powder consisting of Ni and SrRuO3 powder was inserted between these materials and the Ni electrode in order to connect them, and electrical power was passed through the electrodes from the SPS equipment. The open-circuit voltage (V OC) values of a single module in which TE materials were connected to the Ni electrodes by using pressed Ni powder was 82.7?mV, and the maximum output current (I max) and maximum output power (P max) were 212.4?mA and 6.65?mW at ??T?=?470?K, respectively. On the other hand, V OC of a single module in which TE materials and an Ni electrode were connected with a mixed powder (Ni:SrRuO3?=?6:4 volume fraction) was 109?mV, and I max and P max were 4034?mA and 109?mW at ??T?=?500?K, respectively. These results indicate that the resistance at the interface between the TE materials and the Ni electrode can be decreased and the output power can be increased by application of a buffer layer consisting of Ni and SrRuO3. 相似文献
100.
The selective production of lactic acid by anaerobic acidogenesis with low pH control was examined using a chemostat culture. By decreasing culture pH to 3.5 in a chemostat culture containing mixed microbial populations for anaerobic acidogenesis, heterolactic fermentation became dominant, resulting in the selective production of lactic acid and ethanol. This phenomenon was reversible between the acidic and neutral conditions, and was not affected by the dilution rate. The extremely low pH operation was effective for selective lactic acid production in anaerobic acidogenesis. 相似文献