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11.
Sarker PK Takahashi J Kawamoto Y Obayashi Y Kaneko T Kobayashi K 《International journal of molecular sciences》2012,13(1):1006-1017
Aqueous solutions of isovaline and its precursor molecule, 5-ethyl-5-methylhydantoin, were irradiated with ultraviolet and γ-ray photons, to evaluate their structural stability against space radiation. The degree of photolysis was measured and irradiation products were identified using chiral, reversed-phase and ion-exchange high-performance liquid chromatography. The experimental results show that the degree of photolysis of 5-ethyl-5-methylhydantoin is more significant than that of isovaline under ultraviolet light irradiation, while the results under γ-ray irradiation are the opposite. As the products of isovaline photolysis, aspartic acid, serine, glutamic acid and alanine were dominantly detected. 相似文献
12.
Wataru Tamura Arata Yasuda Ken Suto Masasuke Hosokawa Osamu Itoh Jun-Ichi Nishizawa 《Journal of Electronic Materials》2003,32(10):1079-1084
Effects of Bi doping in PbTe liquid-phase epitaxial layers grown by the temperature difference method under controlled vapor
pressure (TDM-CVP) are investigated. For Bi concentrations in the solution, xBi, lower than 0.2 at.%, an excess deep-donor level (activation energy Ed≈0.03–0.04 eV) appears, and Hall mobility is low. In contrast, for xBi>0.2 at.%, Hall mobility becomes very high, while carrier concentration is in the range of 1017 cm−3. Inductive coupled plasma (ICP) emission analysis shows that, for xBi=1 at.%, Bi concentration in the epitaxial layer is as high as NBi=2.3–2.7 × 1019 cm−3. These results indicate that Bi behaves not only as a donor but also as an acceptor, and the nearest neighbor or very near
donor-acceptor (D-A) pairs are formed, so that strong self-compensation of Bi takes place. Carrier concentration for highly
Bi-doped layers shows a minimum at a Te vapor pressure of 2.2 × 10−5 torr for growth temperature 470°C, which is coincident with that of the undoped PbTe. 相似文献
13.
The catalytic solid-state polymerization of trithane to polythiomethylene has been studied. The polymerization can be initiated by wide varieties of substances such as metal salts, halogen, and active organic halides. The polymerization proceeds in solid-state without topochemical process. The catalytic irreversible degradation of polythiomethylene to dimethyl sulfide and carbon disulfide has been observed. 相似文献
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15.
Kazuyuki Kakegawa Jun-Ichi Mohri Shin-Ichi Shirasaki Koichiro Takahashi 《Journal of the American Ceramic Society》1984,67(1):2-C-3
An organic chelation reagent, cupferron, was used to coprecipitate Ti4+ andZr4+ . After the materials were fired, they were mixed with PbO powder and fired again at high temperatures to obtain Pb(Zr,Ti)03 (PZT). It was confirmed that this method is useful for the preparation of homogeneous PZT having no compositional fluctuations. No coexistence range of the tetragonal and rhombohedral phases was observed in the PZT compositions near the morphotropic phase boundary. 相似文献
16.
Yamada Jun-Ichi Machida Susumu Mukai Takaaki Kano Hiroyuki Sugiyama Koichi 《Electronics letters》1979,15(19):596-597
Modulation experimenting on a buried-stripe (b.s.) InGaAsP laser emitting at 1.3 ?m was carried out up to 2 Gbit/s. The b.s. laser is free from relaxation oscillation, which degrades modulated optical pube waveforms, especially at high data rates. The repeater gain of 1.6 Gbit/s transmission systems is improved by 9 dB compared with previously reported experiments. Modulation characteristics up to 2 Gbit/s are reported. 相似文献
17.
Long-span single-mode fibre transmission experiments at 1.3 ?m have been refined toward higher digit rate and longer fibre span. Error-rate against receiving optical level characteristics showed that optical power penalties at 100 Mbit/s, 1.2 Gbit/s and 1.6 Gbit/s are negligible, even after 30 km, 23 km and 13 km fibre transmission, respectively. 相似文献
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19.
Hidaka T Ishikawa A Kojou J Ikari T Ishikawa Y Minamide H Kudoh A Nishizawa J Ito H 《The Review of scientific instruments》2007,78(8):086109
A simple instrument has been developed to carry out temperature dependent submillimeter/terahertz-wave spectroscopy using a polyvinylidene fluoride flexible hollow waveguide and an eggplant-shape launching lens. 相似文献
20.
Niitsuma J Sekiguchi T Yuan XL Awano Y 《Journal of nanoscience and nanotechnology》2007,7(7):2356-2360
We demonstrate a novel method of processing carbon nanotubes using a variable pressure scanning electron microscope. Lines were processed in a nanotube film by electron beam irradiation in oxygen gas and nitrogen gas. The processing mechanism can be explained in terms of gas ion sputtering and chemical reaction. In this experiment, the narrowest line width of 120 nm was achieved in a nitrogen atmosphere. 相似文献