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691.
Ming Zhu Xiao Liu Baijun Liu Zhenhuan Jiang Toshihiko Matsumoto 《Polymer Bulletin》2011,67(9):1761-1771
A new diamine monomer, 1,5-bis[4-(4-aminophenoxy)]benzoyl-2,6-dimethoxynaphthalene, was synthesized via a Friedel–Crafts acylation
reaction followed by an aromatic nucleophilic substitution reaction. Six ether–ketone linked polymers, named as poly(ether
ketone azomethane)s and poly(ether ketone imide)s, were successfully prepared through the polycondensations of the diamine
monomer with dialdehydes and dianhydrides, respectively. These naphthylated polymers exhibited high T
g values (142–288 °C), due to their bulky and rigid chemical structure. Meanwhile, they showed good thermal stability and improved
solubility. Typically, some of them were casted into thin flexible film and showed high moduli. 相似文献
692.
Ni-P alloy/multiwalled carbon nanotube (MWCNT) composite films were fabricated on acrylonitrile butadiene styrene (ABS) resin by electroless plating and their microstructures, adhesion strengths, and friction properties were investigated. Various types of MWCNTs were used. In addition, various electroless plating baths were prepared to form Ni-P alloy matrices with various phosphorus contents. To enhance the adhesion strength, the ABS resin substrate was subjected to roughening treatment. The microstructures of the composite films were examined by scanning electron microscopy and X-ray diffraction. Their adhesion strengths were measured by tensile tests. The friction properties of the composite films were investigated using the ball-on-plate method. Ni-P alloy/MWCNT composite films containing various types of MWCNTs and with Ni-P alloy matrices having various phosphorus contents were fabricated on the ABS resin substrates by electroless deposition. The adhesion strength between the Ni-P alloy/MWCNT composite films and the ABS resin substrate was more than 1300 N cm− 2. The Ni-P alloy/MWCNT composite films had considerably lower friction coefficients than the Ni-P alloy films. The friction coefficients of the composite films were significantly affected by the type of MWCNTs used. 相似文献
693.
Kouji Shiina Tsutomu Kawamura Masaya Ohtsuka Tadashi Mizuno Masakazu Hisatsune Kenji Ogura Kouichi Tanimoto Toshihiko Fukuda Yasuhiko Minami Shoichi Moriya Haruki Madarame 《亚洲传热研究》2007,36(1):38-55
In a branch pipe with one closed end, the cavity flow penetrates into the branch pipe from the main loop and a thermal boundary layer occurs because the cavity flow is a hot fluid, but heat removal causes a colder fluid in the branch pipe. This thermal stratification may affect the structural integrity. Therefore, a pipe design standard to suppress thermal fatigue should be established. The pipe design standard consists of the maximum penetration depth Lsv and the minimum penetration depth Lsh. In order to establish an evaluation method for Lsh, a visualization test and a temperature fluctuation test were carried out. A theoretical formula for thermal stratification was introduced from the heat balance model. Then the model was used to obtain an empirical equation from the map of fluid temperature fluctuation. This method can predict the vortex penetration depth by cavity flow in horizontal branch pipes. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res, 36(1):38–55, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20135 相似文献
694.
This study analyzes the impact of an electricity grid interconnection between Korea and Japan on their energy systems. Both countries seriously consider energy security as the most important policy issue because of a lack of domestic energy resources. In addition, public concern for the environment is recently rising up in response to the global warming. Electricity grid interconnection has strong potential to cope with such complicated problems cost-effectively. We have developed the interconnection model, which includes the electricity grid interconnection between the electricity sectors of Korea and Japan, considering both technological and economic efficiency. The result of the study reveals the significant cost-effectiveness of the interconnection, in particular, under stringent condition such as nuclear phase-out in Japan and CO2 emission target in Korea and Japan. In the case that Japan's nuclear power plants will be phased out, the interconnection attains further cost reduction of constructing substitutive thermal power plants. On the other hand, when Korea and Japan set a joint CO2 emission target, it achieves the emission target more efficiently than they reduce the emission individually. 相似文献
695.
Natural killer (NK) T cells are well known to play important roles in both tumor rejection and the defense against infectious. Therefore, the antitumor potential of NKT cell-activating antigens have been the focus for the development of NKT cell-based immunotherapies. Up to now, several studies have revealed that the administrations of glycolipids (e.g. α-galactosylceramide) can successfully treat certain metastatic tumors. However, liver injuries appeared upon the application of these antigens. We previously examined the potential of using β-glucosylceramide (β-GlcCer) to inhibit tumor metastasis to the liver. The aim of this study was to determine the antimetastatic effects of β-GlcCer and its impact on the activation of NKT cells. Intraperitoneal administration of β-GlcCer enhanced the production of interferon-γ from hepatic lymphocytes containing NKT cells, and increased the cytotoxicity of hepatic lymphocytes against tumor cells. Moreover, β-GlcCer administration suppressed the hepatic metastasis of tumors in wild type (WT) mice, but not in CD1d (-/-) or Jα18 (-/-) mice. The drawback associated with the other glycolipids in liver injury was not noted in WT mice treated with the continuous daily administration of β-GlcCer for 2 weeks. The present study demonstrated that β-GlcCer treatment activates invariant NKT cells, thus resulting in the inhibition of tumor metastasis. 相似文献
696.
H Kosugi K Hanihara T Suzuki T Hongo J Yoshinaga M Morita 《The Science of the total environment》1988,76(2-3):109-115
Nineteen elements (Al, B, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, Sr, Ti, V and Zn) were analyzed in excavated bone (rib) of the Edo era (a Japanese historical era, 300-120 BP (before present] from different burial conditions in Tokyo, and in contemporary Japanese bone (rib) obtained from autopsy cases. The elemental composition of the excavated bones varied according to their burial conditions. The concentration of soil-related elements such as Fe, Mn, Co and Ti in the bone was lowest in the samples in the "wooden coffin in a stone room", next lowest in the "funeral urn with mud", and highest in the "wooden coffin full of mud". The Pb concentration was higher in excavated bones than in contemporary bones and much higher, by as much as several tens micrograms/g, in the bones in the "wooden coffin in a stone room" and in the "funeral urn with mud". These results strongly support the notion that Japanese in the city of Edo were highly polluted by environmental lead. 相似文献
697.
Takeshi Kobayashi Masaaki Ichiki Toshihiko Noguchi Ryutaro Maeda 《Thin solid films》2008,516(16):5272-5276
The present paper describes a Pt/LNO/PZT/LNO/Pt/Ti/SiO2 multilayers deposited on 4-inch Si wafers. We have evaluated the variation of the deflection of the Si wafers with deposition of each of the thin films. The deposition of the multilayers has resulted in downward deflection (center is higher than edge) of the Si wafers. The multilayers have been also deposited onto SOI wafers and fabricated into piezoelectric micro cantilevers through MEMS bulk micromachining. The micro cantilevers have shown the upward deflection. We have characterized the ferroelectric and piezoelectric properties of the PZT thin films through electrical tests of the micro cantilevers. The dielectric constant, saturation polarization, remanent polarization and coercive field were measured to be 1050, 31.3 μC/cm2, 9.1 μC/cm2 and 21 kV/cm, respectively. The transverse piezoelectric constant, d31, was measured to be − 110 pm/V from the DC response of the micro cantilevers. 相似文献
698.
本文介绍的联用分析系统是将超临界流体萃取(SFE)系统与超高效液相色谱(UHPLC)系统联用。使用在线SFE-UHPLC系统,可以完成对胡椒粉中胡椒碱成分的高速萃取和分析。整个分析过程包括萃取时间在内只需要7min。将此方法的萃取回收率与其他萃取方法进行比较,SFE方法得到的回收率与其他方法相当。这种在线SFE-UHPLC方法操作简单,分析速度快。这一方法对于分析固体样品中的化合物组分非常有用,可以有效避免繁琐的样品预处理过程。 相似文献
699.
We have developed a new photodisplacement microscope system for practical use that achieves high-sensitivity simultaneous real-time imaging of surface and subsurface structures from a single space-frequency multiplexed interferogram. In this system a linear region of photothermal displacement is excited on the sample surface for subsurface imaging by a line-focused intensity-modulated laser beam. Surface information such as reflectivity and topography along with the displacement is detected with a charge-coupled device sensor-based parallel heterodyne interferometer. Surface and subsurface information components are space-frequency multiplexed into the sensor signal as orthogonal functions based on a frequency-optimized undersampling scheme, allowing each to be discretely reproduced by using a real-time Fourier analysis technique. Preliminary experiments demonstrate that this system is effective, simultaneously imaging reflectivity, topography, and photodisplacement for the detection of subsurface lattice defects in silicon, at a remarkable speed of only 0.26 s/256x256 pixel area. This new microscope is promising for nondestructive hybrid surface and subsurface inspection and other applications. 相似文献