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排序方式: 共有58条查询结果,搜索用时 31 毫秒
1.
A compact high-resolution optical heterodyne interferometer combining a two-frequency light module and a minute optical system
is described. The light module, which generates two independent frequencies of light, is fabricated by proton exchange method
on LiNbO3 substrate. We report an experiment evaluating measurement accuracy using a micro-displacement measurement system which incorporates
this interferometer. Results of the experiment with a standard thickness sample show high thermal stability with maximum measurement
error of 1.8 nm at a temperature from 19°C to 33°C. The system was used to measure the hysteresis of a piezoelectric element
for displacements of several nm, thereby making it possible to analyze the system quantitatively in practice. 相似文献
2.
A method for the preparation of insulin derivatives which have protected sulfhydryl group(s) at definite site(s) on the molecule is described. Porcine insulin reacts with S-acetylmercaptosuccinic anhydride to afford four species of insulin derivatives that have 2 (or 3)-acetylmercapto-3-carboxypropanoyl group(s) at i) Gly(A1), ii) Gly(A1) and Phe(B1), iii) Gly(A1) and Lys(B29), and iv) Gly(A1), Phe(B1) and Lys(B29) positions. The derivatives are efficiently separated in a preparative scale by anion-exchange high-performance liquid chromatography on a TSKgel DEAE-2SW column. The four derivatives are all readily deacetylated with hydroxylamine to give the corresponding sulfhydryl insulin derivatives. 相似文献
3.
Sun-Chan Jeong Ichiro Katayama Hirokane Kawakami Yutaka Watanabe Hironobu Ishiyama Nobuaki Imai Yoshikazu Hirayama Hiroari Miyatake Masao Sataka Hiroyuki Sugai Satoru Okayasu Shin-Ichi Ichikawa Katsuhisa Nishio Shinichi Mitsuoka Takamitsu Nakanoya Takashi Hashimoto Takanori Hashimoto Masahito Yahagi 《Solid State Ionics》2009,180(6-8):626-630
The diffusion coefficients of Li in the NaTl-type Li intermetallic compound of β-LiGa have been measured by using a short-lived radioactive diffusion tracer. As the tracer, the α-emitting radioisotope of 8Li delivered as the energetic and pulsed beam from Tokai Radioactive Ion Accelerator Complex (TRIAC) was implanted into the β-LiGa compounds with the composition in the range of about 43 to 54 at.% Li. By analyzing the time-dependent yields of the α-particles measured according to the repetition cycle of the beam, the tracer diffusion coefficients were extracted over the wide range of Li composition. Abnormal composition-dependence of Li diffusion coefficients in β-LiGa was observed; the stoichiometric β-LiGa showed the highest diffusivity of Li. By referring to the composition-dependent diffusivity of Li in the iso-structural β-LiAl and β-LiIn, we could identify the abnormal diffusion of Li in very Li-poor composition of β-LiGa. The anomaly has been discussed qualitatively in terms of the formation of defect complex and the interaction between the constitutional defects. 相似文献
4.
K. Hirose M. Ejima T. Fujibayashi Y. Fujii K. Futatsukawa O. Hashimoto T. Ishikawa S. Kameoka H. Kanda F. Kato S. Kinoshita T. Kinoshita T. Kon O. Konno K. Maeda A. Matsumura Y. Miura F. Miyahara H. Miyase T. Nakabayashi S.N. Nakamura H. Nomura K. Nonaka A. Ohtani Y. Okayasu M. Oyamada A. Sasaki H. Shimizu T. Takahashi T. Tamae H. Tamura T. Terasawa H. Tsubota K. Tsukada D. Uchida M. Ukai M. Wakamatsu T. Watanabe H. Yamauchi H. Yamazaki K. Yawata 《Physics letters. [Part B]》2009
5.
T. Watanabe P. Bydžovský K. Dobashi S. Endo Y. Fujii O. Hashimoto T. Ishikawa K. Itoh H. Kanda M. Katoh T. Kinoshita O. Konno K. Maeda A. Matsumura F. Miyahara H. Miyase T. Miyoshi K. Mizunuma Y. Miura S.N. Nakamura H. Nomura Y. Okayasu T. Osaka M. Oyamada A. Sasaki T. Satoh H. Shimizu M. Sotona T. Takahashi T. Tamae H. Tamura T. Terasawa H. Tsubota K. Tsukada M. Ukai M. Wakamatsu H. Yamauchi H. Yamazaki 《Physics letters. [Part B]》2007
6.
Ion irradiation effects on improvement of flux-pinning properties for quenched and melt growth YBCO samples (QMG-materials)
were studied. Irradiation with 16MeV protons was performed up to a dose of 1×1016 p/cm2. The effective activation energies of vortices are expressed with the formula, Ueff=g(T)h(H)f(J) ∝ (J/Jc)−∝* [1-(T/Tx)2]2/3*H−1/3 at lower irradiation doses below 5×1015 p/cm2. The J-dependence of Ueff changes from power-law to quesi-exponential dependence with an increment of irradiation dose. 相似文献
7.
[reaction: see text] We have established an enantioselective synthesis of both C2 symmetric and unsymmetric tetra-ortho-substituted axially chiral biaryls through rhodium-catalyzed double [2 + 2 + 2] cycloaddition (up to >99% ee). This method serves as an attractive new route to enantioenriched tetra-ortho-substituted axially chiral biaryls in view of the one-step access to substrate diynes and tetraynes starting from readily available alkynes. 相似文献
8.
Nanami Hara Shu Fujisawa Mizuki Fujita Mikako Miyazawa Kazuma Ochiai Satoshi Katsuda Tetsuya Fujimoto 《Tetrahedron》2018,74(2):296-302
Kinetic resolution of secondary alcohols by benzoylation using a phosphinite derivative of (1S,2R)-1-amino-2-indanol as the catalyst was investigated. The aminophosphinite catalyst is effective for the kinetic resolution of aryl cycloalkyl carbinols with a small number of examples for organocatalytic kinetic resolution to achieve resolution with s = up to 44. Although the benzoylation of phenylalkanols proceeded with a low selectivity, 1-arylalkanols bearing at least one substituent at the ortho position on the benzene ring or a branched alkyl group on the carbinol carbon were resolved with acceptable selectivity. 相似文献
9.
S. Kawai E.S. Otabe M. Kiuchi T. Matsushita T. Nomura H. Yamauchi T. Motohashi S. Okayasu 《Physica C: Superconductivity and its Applications》2009,469(15-20):1224-1228
Critical current density was measured for oxygen-controlled (Bi, Pb)-2223 single crystals before and after the irradiation with gold ions in a magnetic field parallel to the irradiation-induced defects along the c-axis. Eleven specimens prepared in different annealing conditions were measured. The condensation energy density of each specimen was evaluated from the observed critical current density by using the summation theory of pinning forces of columnar defects and the flux creep theory. It was found that the specimen heat-treated at 1 atm in oxygen atmosphere has the highest condensation energy density among all specimens. Hence, it is speculated that the optimum oxygen pressure for the anneal is around 1 atm. 相似文献
10.
The travelling performance of rigid wheels on sand stratum is measured using two kinds of surface material, i.e. steel and steel coated with rubber. A new method for measuring the displacement of soil beneath the wheel has been developed using small polyester film markers. The trajectories of soil particles beneath the wheels are approximated by an exponential function and the fluctuations in the drawbar pull are represented by a sinusoidal function. The amplitude and basic wavelength of the fluctuation in the drawbar pull are discussed for both types of wheels. 相似文献