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71.
72.
Low-noise operation of a 9-GHz hybridly mode-locked laser diode is demonstrated. The integrated timing jitter was 47 fs (10 Hz to 10 MHz) and 86 fs (10 Hz to 4.5 GHz), with a pulse width of 6.7 ps. The noise performance as a function of filter bandwidth and oscillator noise is also addressed. 相似文献
73.
Introduction of a hydrogen-bonding substituent to 1-cyanonaphthalene and alkene resulted in the selective formations of endo-photocycloadducs. Furthermore, the yield and selectivity were improved as the reaction temperature was lowered. 相似文献
74.
K. Yatsui M. Yatsuzuka T. Fujii M. Yokoyama M. Masuzaki T. Tsuzuki K. Narihara A. Mohri 《Physics letters. A》1979,73(4):321-323
We study experimentally the interaction of a current-modulated relativistic electron beam with a mirror-confined plasma. A high-power transmitter (500 MHz, 1 GW) is developed. Rapid heating takes place up to ≈ 900 eV, which is interpreted as a lower-hybrid parametric instability. 相似文献
75.
New polyesters containing phenoxaphosphine rings were prepared from 2,8-dichloroformyl-10-phenylphenoxaphosphine 10-oxide (I) and bisphenols by interfacial polycondensation. The investigations of polymerization conditions using (I) and bisphenol A showed that addition of quarternary ammonium salts was effective in the preparation of polyesters. The highest viscosities were obtained when tetrabutylammonium chloride was used as accelerator. Some of the resulting polyesters had reduced viscosities of 0.85–1.92 dl/g in DMA of m-cresol and they dissolved in chloroform, m-cresol and nitrobenzene. These polymers melted in the range of 288–355′, hardly degraded below 400′ and were self-extinguishing. They appeared to have better thermal stability than linear open-chain phosphorus-containing polyesters. 相似文献
76.
Shigeyuki Mayama Toshikazu Tani Tamio Ueno Kazumasa Hirabayashi Tadakazu Nakashima Hiroshi Fukami Yukio Mizuno Hiroshi Irie 《Tetrahedron letters》1981,22(22):2103-2106
The major phytoalexin from oat leaves has been identified as 2-[2-(4-hydroxyphenyDethenyl] -6-hydroxy-4H-3,1-benzoxazin-4-one (). 相似文献
77.
Archiv der Mathematik - 相似文献
78.
Moment bounds for stationary mixing sequences 总被引:11,自引:0,他引:11
Ryozo Yokoyama 《Probability Theory and Related Fields》1980,52(1):45-57
79.
We investigated the effect of charge-charge interactions on the mobilities of rhodamine 6G (R6G), Nile Red, sulforhodamine B, and Oregon Green 514 (ORG) guest molecules within a silica sol-gel host as the guest charge progressed from positive to neutral to negative. Through classification of the mobility as fixed, tumbling, or intermediate behavior, we were able to distinguish differences in surface attraction as the guest charge was varied. On the basis of our results, an attractive charge (as tested by cationic R6G) does not contribute significantly to mobility within dry films. However, an increase in the cationic influence is observed in water-equilibrated environments. A comparison of ORG in dry and water- and phosphate-buffer-equilibrated films indicates that charge repulsion does significantly increase dye rotational mobility (to a maximum of 24 +/- 3% tumbling molecules). However, in view of the percentage of tumbling molecules found, charge-charge interactions do not appear to be the dominant force controlling guest mobility. 相似文献
80.
Cho T Yoshida M Kohagura J Hirata M Numakura T Higaki H Hojo H Ichimura M Ishii K Islam KM Itakura A Katanuma I Nakashima Y Saito T Tatematsu Y Yoshikawa M Kojima Y Tokioka S Yokoyama N Tomii Y Imai T Pastukhov VP Miyoshi S;GAMMA Group 《Physical review letters》2005,94(8):085002
Vortexlike turbulent structures in hot-ion mode plasmas with several keV are observed in the case with a radially produced weak shear of electric fields E(r). However, a strong E(r) shear formation due to a high ion-confining potential phi(c) production clears up these vortices together with plasma-confinement improvement and disappearance of both drift-wave and turbulencelike Fourier spectral signals. These findings are based on three-time progress in phi(c) in comparison to phi(c) attained 1992-2002. The significant advance of phi(c) is well extended in line with proposed potential-formation physics scalings. 相似文献