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11.
The Global Oscillation Network Group (GONG) project estimates the frequencies, amplitudes, and linewidths of more than 250,000 acoustic resonances of the sun from data sets lasting 36 days. The frequency resolution of a single data set is 0.321 microhertz. For frequencies averaged over the azimuthal order m, the median formal error is 0.044 microhertz, and the associated median fractional error is 1.6 x 10(-5). For a 3-year data set, the fractional error is expected to be 3 x 10(-6). The GONG m-averaged frequency measurements differ from other helioseismic data sets by 0.03 to 0.08 microhertz. The differences arise from a combination of systematic errors, random errors, and possible changes in solar structure.  相似文献   
12.
Injection of ethylenediaminetetraacetic acid into spayed rats or its use in phosphorylase extraction increases the activity of glycogen-phosphorylase a in uterine smooth muscle tissue. Since the total phosphorylase activity is not increased, the increase in phosphorylase a appears to result from a conversion of inactive phosphorylase b to the active form of the enzyme.  相似文献   
13.
陈杰  龚子同  Blume HP 《土壤》2004,36(3):225-231
气候变化导致南极海洋气候区冰川消退、多年积雪融化,为新的土壤形成与分布提供了潜在的母质基础与发展空间;地表和土壤内部水分活动在时间和空间上的加强促进了以自由水为基础的土壤过程和冰缘地貌过程;由气候变化引发的低等植物生境、群落结构变化、初级生产力与生物量的提高、海洋脊椎动物迁徙和栖息地的变迁,影响了本区土壤有机质积累过程以及土壤有机质结构与性状。已有的证据表明,气候变化正对南极海洋气候区土壤发生、发育及演变产生重要影响。  相似文献   
14.
Doppler velocity observations obtained by the Global Oscillation Network Group (GONG) instruments directly measure the nearly steady flows in the solar photosphere. The sun's differential rotation is accurately determined from single observations. The rotation profile with respect to latitude agrees well with previous measures, but it also shows a slight north-south asymmetry. Rotation profiles averaged over 27-day rotations of the sun reveal the torsional oscillation signal-weak, jetlike features, with amplitudes of 5 meters per second, that are associated with the sunspot latitude activity belts. A meridional circulation with a poleward flow of about 20 meters per second is also evident. Several characteristics of the surface flows suggest the presence of large convection cells.  相似文献   
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