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排序方式: 共有706条查询结果,搜索用时 31 毫秒
51.
Hidemitsu Aoki Kazuki Miyano Daisaku Yano Kazuhiko Sano Koji Yamanaka Chiharu Kimura Takashi Sugino 《Polymer Engineering and Science》2007,47(10):1666-1670
Biological and chemical sensor with a rapid response in microlevel test is required for health and environmental monitor. A novel sensing due to porous ion exchanger with three-dimensional acceptor has been first attempted to develop a high-performance sensor. This porous monolith type ion exchanger has an open-cellular monolith structure with 5–50-μm diameter pores. The trace amount of inorganic ions dissolved in aqueous solutions can be quantitatively determined with the impedance given by the monolith, which attracts and adsorbs the ions rapidly. We have succeeded in detecting ions with a concentration as low as 10−7 mol. The porous ion exchanger has a potentiality as a high-performance device for biological and chemical sensing. POLYM. ENG. SCI., 47:1666–1670, 2007. © 2007 Society of Plastics Engineers 相似文献
52.
We analyzed the dietary fish and marine mammal oil supplements purchased from Japanese markets for hexabromocyclododecane (HBCD); 20 brands were analyzed by liquid chromatography–tandem mass spectrometry (LC/MS/MS). HBCD was detected in 15 of 22 samples, and the concentrations of all the HBCD isomers (α, β, and γ) ranged from <0.9 to 67 ng/g lipid weight. α-HBCD was the dominant residue among the HBCD isomers. However, the composition of HBCD isomers varied according to the sample type. We found that 1 sardine oil brand and 2 shark liver oil brands extracted from fish captured in seawater around Japan contained relatively high levels of HBCD, indicating that both the surface and deep seawaters around Japan may have been contaminated with HBCD. 相似文献
53.
K. Kawanishi A. Tsuge K. Kuwabara O. Ukai N. Nakamori 《Nuclear Engineering and Design》1990,120(2-3):259-269
Scaled experiments on small break, loss-of-coolant accidents have been conducted. The tests simulated loss-of-coolant accidents (LOCAs) resulting from a 0.53% and a 0.13% communicative break in the cold leg and the pressurizer power operated relief valve (PORV). The thermal-hydraulic behavior such as natural circulation and reflux condensation cooling during a small break LOCA has been investigated.
A new computer program CANAC-II (a Computer Analysis Program of Natural Circulation for multi-loop systems) has been developed and verified based upon comprehensive tests. A drift flux model was applied for two-phase flow in CANAC-II. It also has a shorter computer running time than the real time. 相似文献
54.
Renato Martins da Silva Bárbara Della Noce Camila Fernanda Waltero Evenilton Pessoa Costa Leonardo Araujo de Abreu Naftaly Wang’ombe Githaka Jorge Moraes Helga Fernandes Gomes Satoru Konnai Itabajara da Silva Vaz Jr. Kazuhiko Ohashi Carlos Logullo 《International journal of molecular sciences》2015,16(1):1821-1839
55.
Sobi Asako Takahisa Sakae Masahito Murai Kazuhiko Takai 《Advanced Synthesis \u0026amp; Catalysis》2016,358(24):3966-3970
Mild and simple catalytic systems consisting of molybdenum(VI) dichloride dioxide [MoO2Cl2] as a catalyst and a phosphine as reductant have been developed for the stereospecific deoxygenation of epoxides to alkenes. The reactions using 1,2‐bis(diphenylphosphino)ethane (dppe) and triphenylphosphine (PPh3) proceed with retention and inversion of stereochemistry, respectively. The mild reaction tolerates the presence of various functional groups and affords stereodefined substituted olefins in good yields.
56.
For the construction of a microwave-assisted organic synthesis plant, it is necessary to know the dielectric properties of the reaction system. Measurements of the dielectric properties of lactic acid aqueous solution, anhydrated lactic acid, oligo(lactic acid) and water, which are constituent materials in the polycondensation of lactic acid, confirm that dielectric properties decrease as reaction progresses. Calculated microwave penetration depths, obtained from the dielectric properties, show that microwaves penetrate deeply into the reaction system. This work should be useful for the development of microwave-assisted organic syntheses in the chemical industry. 相似文献
57.
Akutsu K Hori S 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2004,45(4):175-183
Polybrominated diphenyl ethers (PBDEs) have been used worldwide as additive flame retardants in polymeric materials. Commercial products consist predominantly of deca-, octa-, and pentabromodiphenyl ether mixtures. PBDEs are resistant to degradation in the natural environment and Penta-BDE in particular accumulates in the fatty tissues of fish, birds and mammals (including humans). Several toxic effects on the thyroid system or on neurodevelopment have been reported in experimental animals exposed to PBDEs. It is likely that human exposure is predominantly through the ingestion of contaminated food and/or mother's milk. The potential health effects of dietary exposure to PBDEs have now become a great concern because of the increasing PBDE levels in the biosphere. In this review, published information on the toxicology of PBDEs, levels in foodstuffs and human milk, and analytical methods has been compiled. 相似文献
58.
Toshiaki Arai Narihiro Morosawa Kazuhiko Tokunaga Yasuhiro Terai Eri Fukumoto Takashige Fujimori Tatsuya Sasaoka 《Journal of the Society for Information Display》2011,19(2):205-211
Abstract— The stability and reliability of oxide‐semiconductor TFTs were investigated. The contact material to the oxide semiconductor affected the thermal stability of the TFT, and a molybdenum‐contact source/drain showed good stability. And the passivating film and TFT structure affected the stability against bias stress and humidity stress, and dc‐sputtered Al2O3 passivation and fully covered channel structure with an etching stopper or source/drain showed good reliability. Moreover, high photo‐stability was confirmed by the bias‐enhanced photo‐irradiation stress test. An 11.7‐in.‐diagonal qHD AMOLED display was demonstrated to provide an applicable solution for a large‐sized OLED and an ultra‐high‐definition LCD‐TV mass production. 相似文献
59.
Kazuhiko Suzuki S. Seto A. Iwata M. Bingo T. Sawada K. Imai 《Journal of Electronic Materials》2000,29(6):704-707
The electron drift mobility of undoped Cd0.9Zn0.1Te grown by high-pressure Bridgman method is measured by a time-of-flight technique. The sample shows a room temperature mobility
and mobility lifetime product of 950 cm2/Vs and 1.6 × 10−4cm2/V, respectively. The mobility increases monotonically with decreasing temperature to 3000 cm2/Vs at 100 K. The dominant scattering mechanism for the electron transport is discussed by comparing with the theoretical
mobility obtained by iterative solution of the Boltzmann equation. 相似文献
60.
The heterogeneous nature of hardwood lignin was shown by visualizing the deposition process of p-hydroxyphenyl (H) lignin in the differentiating xylem of magnolia, beech, lilac and poplar. When p-glucocoumaryl alcohol-[arom. ring-2-3H], an efficient precursor of H units in lignin, was administered to the differentiating xylem of these trees, radioactivity was incorporated in the compound middle lamella region of vessel and fiber cell walls. The deposition of H units occurs only in the early stage of cell wall formation when the outer layer of the secondary wall is formed. H lignin deposits mainly within pectic substances and hemicellulose gel to form a highly condensed structural moiety. 相似文献