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661.
662.
Kaneda Y Yarborough JM Li L Peyghambarian N Fan L Hessenius C Fallahi M Hader J Moloney JV Honda Y Nishioka M Shimizu Y Miyazono K Shimatani H Yoshimura M Mori Y Kitaoka Y Sasaki T 《Optics letters》2008,33(15):1705-1707
We report an all-solid-state laser system that generates over 200 mW cw at 244 nm. An optically pumped semiconductor laser is internally frequency doubled to 488 nm. The 488 nm output is coupled to an external resonator, where it is converted to 244 nm using a CsLiB(6)O(10) (CLBO) crystal. The output power is limited by the available power at 488 nm, and no noticeable degradation in output power was observed over a period of several hours. 相似文献
663.
M. Yamamoto M. Hoshi J. Takada A. Kh. Sekerbaev B. I. Gusev 《Journal of Radioanalytical and Nuclear Chemistry》1999,242(1):63-74
Field missions were sent to Semipalatinsk City and several settlements near the former Semipalatinsk nuclear test site to
investigate the current radioactive contamination levels of the land coming from long-lived radionuclides. The soil was sampled
at about 20 sites, including some settlements such as Mostik, Dolon and Chagan, forest and pasture areas, along the roads
from Semipalatinsk City to Kurchatov City and to Korosteli settlement in the direction of the Altai District. The radioactivities
of137Cs,238Pu and239,240Pu as well as240Pu/239Pu atomic ratios in the soil were determined by non-destructive γ-ray spectrometry and radiochemical separation followed by
α-ray spectrometry and/or ICP-MS, respectively. The results showed a distinction of137Cs and239,240Pu inventories in soil depending on the site where we visited. While the overall137Cs levels were as same as or slightly lower than the domestic global fallout level (3·103–7·103 Bq/m2),239,240Pu levels at some sites were several to a few ten times higher than the domestic level (40–120 Bq/m2). The atomic ratios of240Pu/239Pu in the soil were in the range of 0.024–0.125, which were significantly lower than the value of 0.18 commonly accepted for
global fallout Pu. 相似文献
664.
Hiroshi Fukutomi Takeshi Yamamoto Kazushi Nonomura Kazuyoshi Takada 《Interface Science》1999,7(2):141-146
In order to understand the factors dominating grain boundary sliding, stress change tests and stress reversal tests were conducted on aluminum bicrystal specimens with high angle grain boundaries. It is found that small change in stress results in the remarkable change in the rate of grain boundary sliding. Stress reversal tests showed that grain boundary slide hardening does not work for the sliding to the direction opposite to that before the stress reversal. Mean internal stresses for the dislocations contributing to grain boundary sliding are experimentally measured by a method consisting of stress change and annealing. It is found that the velocity of dislocations in the grain boundary is in proportion to the mean effective stress. 相似文献
665.
Hiroya Takada Kouichi Ohe Sakae Uemura 《Angewandte Chemie (International ed. in English)》1999,38(9):1288-1289
Up to 99 % de is obtained in the imidation of diaryl sulfides bearing a chiral oxazolinyl moiety at the ortho position. The corresponding N-p-tosylsulfimides are produced upon use of chloramine T trihydrate in the presence of Cu(OTf)2 as catalyst [Eq. (1)]. OTf=trifluoromethanesulfonate; Ts=toluenesulfonyl. 相似文献
666.
Optical Review - An optical imaging system for color mapping of the bidirectional reflectance distribution function (BRDF) using a line scan camera is proposed here that can detect slight BRDF... 相似文献
667.