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101.
The effects of grain size, volume fraction of the α (fcc) phase in the β (bcc) matrix, and thermal stability on low thermal expansion (LTE) properties of Cu-Zn-Al shape memory (SM) alloys induced by cold rolling were investigated by dilatometry, optical microscopy, differential scanning calorimetry, and electrical conductivity measurements. The alloys with the larger grains showed a superior two-way memory (TWM) effect, wider LTE temperature intervals with excellent thermal stability under 80°C. The α+β two-phase alloys also exhibited a good combination of cold workability and LTE properties. These results suggest that the Cu-Zn-Al alloys with high electrical conductivity of about 20% International Annealed Copper Standard (%IACS) have high potential as a new class of Invar alloys that can be applied in various fields.  相似文献   
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103.
In liquor production, barley koji is used a source of saccharification enzymes, nutrition for yeast multiplication, and to impart flavor to the shochu product. Its role is analogous to that of malt in beer and whisky production. In this report, the influence of barley variety and pearling rate on barley koji characteristics is shown. Four Australian varieties (Stirling, Schooner, Arapiles, Grimmett) and one Japanese variety (Nishinohoshi) were evaluated. Significant differences were observed among barley varieties and pearling rate with respect to the amount of koji mycelia produced, enzyme activity and the amino acid composition of the barley koji.  相似文献   
104.
Li  Xinyi  Bao  Jingfu  Huang  Yulin  Zhang  Benfeng  Tang  Gongbin  Omori  Tatsuya  Hashimoto  Ken-ya 《Microsystem Technologies》2018,24(7):2991-2997
Microsystem Technologies - This paper investigates applicability of double raised borders to the piston mode film bulk acoustic resonator (FBAR). It is shown that it offers significant improvement...  相似文献   
105.
This paper proposes a simple technique to suppress the reflection coefficients S11 and S22 of surface acoustic wave (SAW) filters. Two identical SAW filters are sandwiched in between two quadrature hybrids, where their two ports are used as input and output, and others are terminated by matched loads. First, it is shown by simulation that both [S11] and [S22] are suppressed to be less than -20 dB without deteriorating the transmission characteristics. Next, two hybrids using microstrip lines were fabricated, and two RF SAW filters for GSM850 were sandwiched in between them. The result showed that the maximum [S11] within the passband was improved from -12.5 dB to -21.7 dB, i.e., 9.2 dB suppression of [S11] was achieved by sacrificing only the insertion loss of less than 0.6 dB. We also attempted to replace the microstrip lines with lumped elements. In this case, the maximum [S11] within the passband was improved more than 7.5 dB with the increased insertion loss of less than 1.5 dB. Finally, simple discussion is given on the inclusion of the transformer function in the quadrature hybrid.  相似文献   
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107.
A new equivalent circuit is given for the GaAs m.e.s.f.e.t., which includes resistive loss in the feed back elements. The circuit values are given for several 1 ?m-gate GaAs m.e.s.f.e.t.s. A method for fitting s12 to the measured data is described. Finally, the gain and stability factor of several GaAs m.e.s.f.e.t.s. are extrapolated to 24 GHz from the present model.  相似文献   
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109.
Alkaliphilic Mycobacterium sp. strain MHP-1, which can grow on pyrene as a sole carbon and energy source, was isolated from a soil sample. At the optimum pH for growth (pH 9), about 50% of pyrene (final concentration at 0.1% [w/v]) was degraded during 7 d of incubation, and 4,5-phenanthrenedioic acid, 4-phenanthroic acid and phthalic acid were identified as metabolic intermediates. Strain MHP-1 was found to possess aromatic-ring dioxygenase genes, which are highly homologous to the known nidAB genes from pyrene-degrading mycobacteria.  相似文献   
110.
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