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41.
Huiyuan Geng Takahiro Ochi Shogo Suzuki Masaaki Kikuchi Satoru Ito Junqing Guo 《Journal of Electronic Materials》2013,42(7):1999-2005
Bulk multifilled n- and p-type skutterudites with La as the main filler were fabricated using the spark plasma sintering (SPS) method. The thermoelectric properties and thermal stability of these skutterudites were investigated. It was found that the interactions among the filling atoms also play a vital role in reducing the lattice thermal conductivity of the multifilled skutterudites. ZT = 0.76 for p-type La0.8Ba0.01Ga0.1Ti0.1Fe3CoSb12 and ZT = 1.0 for n-type La0.3Ca0.1Al0.1Ga0.1In0.2Co3.75Fe0.25Sb12 skutterudites have been achieved. Furthermore, the differential scanning calorimetry (DSC) results show that there is no skutterudite phase decomposition till 750°C for the La0.8Ba0.01Ga0.1Ti0.1Fe3CoSb12 sample. The thermal stability of the La0.8Ba0.01Ga0.1Ti0.1Fe3CoSb12 skutterudite is greatly improved. Using the developed multifilled skutterudites, the fabricated module with size of 50 mm × 50 mm × 7.6 mm possesses maximum output power of 32 W under the condition of hot/cold sides = 600°C/50°C. 相似文献
42.
Shiv Shankhar Kaundun Satoru Matsumoto 《Journal of the science of food and agriculture》2011,91(14):2660-2663
BACKGROUND: Tea is the most consumed beverage worldwide after water. Yet very little is known about the genetics of tea in comparison with other crop species. Here we have taken advantage of the polymorphic nature of microsatellite DNA to investigate the mode of chloroplast inheritance in tea, Camellia sinensis (L.) O. Kuntze. This is important for the correct interpretation of phylogeny and introgression data as well as assessing the suitability of chloroplast transformation as a means for transgene containment in tea. RESULTS: The study was based on six Japanese tea cultivars, namely Aj2, CK23, Hatsumomiji, Nka05, Yamanoibuki and Kanayamidori used to generate four informative families. The parental pairs in the crosses differed at a single chlroroplast locus with respect to an imperfect microsatellite repeat of 16 nucleotide bases. In agreement with earlier cytological studies, all 61 progeny displayed a cpDNA profile that was consistent with the maternal inheritance of chloroplasts in tea. CONCLUSIONS: The data generated here provide the first molecular evidence of the plastid inheritance in tea. However, we suggest that additional families and polymorphic markers be screened for increasing the confidence in the observed maternal inheritance of chloroplasts in this important crop species. Copyright © 2011 Society of Chemical Industry 相似文献
43.
We determined phase equilibria in the Co-rich Co-Al-W-Ti quaternary system at a temperature range between 900 °C and 1200 °C with a close attention to the thermodynamic stability of the γ′-Co3(Al, W, Ti) (L12) phase, based on micro-structure observation and electron microprobe analysis on bulk alloy samples heat-treated for periods up to 2000 h. In the quaternary system the single phase field of γ′ extends from the Co-Ti binary edge to a composition of Co-5Al-8.5W-8Ti (in at.%) at 900 °C. At the tip of the single phase field, the γ′ phase is in equilibrium with the γ-Co (A1), Co2AlTi (L21) and Co3W (D019) phases. The constructed vertical section of phase diagram between Co-9.4Al-9.6W and Co-16.5Ti indicates that there is a narrow composition range around Co-4.5Al-5.4W-7.5Ti in which the γ single phase field exists at high temperatures above 1200 °C and two-phase of γ+γ′ is thermodynamically stable at low temperatures below 1100 °C. 相似文献
44.
Satoru TakeshitaTatsuya Watanabe Tetsuhiko Isobe Tomohiro SawayamaSeiji Niikura 《Optical Materials》2011,33(3):323-326
YVO4:Bi3+,Eu3+ nanophosphor synthesized by the citrate route shows the photobleaching behavior, i.e., the decrease in photoluminescence intensity under the continuous irradiation of excitation light. This photobleaching property is remarkably suppressed by the washing post-treatment combined with centrifugation and the hydrothermal post-treatment. A relation between the fraction of photobleach and the amount of citrate ions coordinating to metallic ions at the surface of nanoparticles verifies that the photobleaching behavior of YVO4:Bi3+,Eu3+ nanophosphor originates from the redox reaction between the citrate ions and V5+ in YVO4 host crystal. The long-term light fastness test reveals that the hydrothermally treated YVO4:Bi3+,Eu3+ nanophosphor has sufficient photostability for practical use over 15 years outside. 相似文献
45.
Hiroyasu Hotokezaka Noboru Aoyagi Yasuhiro Kawahara Noriko U. Yamaguchi Shinya Nagasaki Ken Sasaki Satoru Tanaka 《Microsystem Technologies》2005,11(8-10):974-979
Laser-induced breakdown spectroscopy (LIBS) has been applied for quantitative analysis of Al2O3, CaCO3 and MgO particles suspended in water. In the single elemental system, the plasma emission intensities of Al, Ca and Mg were linearly increased with concentration of elements in the range of 1.0×10?5–1.0×10?3 M, 1.0×10?4–2.0×10?3 M and 8.0×10?5 –4.0×10?3 M, respectively. We also investigated the concentration dependence of breakdown spectra for suspended mixtures of Al2O3, CaCO3 and MgO particles. The emission lines, such as Al I, Ca I, Ca II and Mg I, were appeared in the LIBS spectrum simultaneously, and each emission peak could be deconvoluted. The plasma emission intensities of Al, Ca and Mg in the multielemental system were also linearly increased with their concentrations in the range of 1.0×10?5–1.0×10?3 M, 1.0×10?4–2.0×10?3 M and 4.0×10?4–2.0×10?3 M, respectively. LIBS was found to be available for quantitative and qualitative measurement of the concentrations of Al2O3, CaCO3 and MgO particles suspended in water. The present results suggest that LIBS is a potentially useful tool for in-situ analysis on particles composition and concentrations for environmental monitoring by the wearable information equipments. 相似文献
46.
Yasunari Nagaki Satoru Itabashi Hideo Mitsui Mototaka Sone 《Electrical Engineering in Japan》1994,114(3):23-32
It has been proposed that vapor-mist dielectrics in which mixing liquid droplets such as tetrachloroethlene in a gas have the ability of increasing flashover, impulse voltage, and of suppressing partial discharge. Vapor-mist methods have been performed on other materials and the effect of the mist can also be obtained on benzene, hexane, and even water as general materials. Although these studies have been carried out, neither the discharge mechanism on vapor-mist nor the reason for the increase of the discharge voltage is understood fully because the mist is of various sizes. On the other hand, agglomeration of water molecules can be studied with the FR-IR method, and are classified into monomer, dimer, trimer (including polymer). Water gives mist stats which are significant in discussing effects. This paper describes states of water mist and their effect under nonuniform field with positive and negative polarities. Water mist in vapor exists as dimer and trimer, and their amount decreases with the reduction of temperature. These mists have no effect on discharge suppression. However, when the mists are formed by space charges, the inception voltage is increased by these mists in the negative polarity. 相似文献
47.
In this paper, we proposed a method to predict the capacity of a heat exchanger by considering static pressure distributions of refrigerants. The thermal network method was modified by adding an equivalent heat generation term into a heat balance equation that was connected with calculated 1D static pressure distributions of refrigerants. An experiment was performed with a heat exchanger having two rows and two passes to verify the accuracy of the proposed method. The result showed the error of the predicted capacity to be less than 1% for an evaporator and less than 2% for a condenser. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(5): 376–390, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10039 相似文献
48.
The linewidth enhancement factor, α, in the Ga1-xInxAs/GaInAsP/InP strained-quantum-well system was calculated and analyzed using density-matrix theory taking into account the effects of band-mixing on both the valence subbands and the transition dipole moments. As a result of numerical calculation, it was found that a reduced linewidth enhancement factor of 1.1 at the gain peak wavelength can be obtained in the tensile strained-quantum-well structure for TM-mode operation. This is due to the higher differential gain and a negligible free carrier plasma effect in the TM-mode compared to that of the TE-mode operating in the compressively strained-quantum-well structure. This calculation agrees with previously reported experimental results 相似文献
49.
50.
Satoru Kuroda 《Computational Complexity》2004,13(1-2):69-89
We characterize iterated log depth circuit classes between AC0 and AC1 by Cobham-like bounded recursion schemata. We also give alternative characterizations which utilize the safe recursion method developed by Bellantoni and Cook. 相似文献