1946年 6卷 第2期
1946, 6(2): 79-85.
doi: 10.7498/aps.6.79
摘要:
In estimating the frequency of oscillation of a positive-grid oscillator, it is usually. assumed that the space charge effect is negligible. Under this assumption, the potential distribution in the space between the plane-parallel electrodes is linear. Thus the electric field in the space is uniform and the average velocity of electron flight can be used to evaluate the frequency of oscillation. The presence of space charge affects the potential distribution in space so that the electric field in this region is no more constant. Hence more exact formula must be used to compute the frequency of oscillation. The calculation is further complicated by the fact that the anode potential is usually made slightly negative with respect to the cathode. In this case, the location of the virtual cathode at which the electrons turn back does not coincide with that if a straight line potential distribution were assumed. The predicated frequency of oscillation is about 10-20 percent lower than that if space charge were neglected.
In estimating the frequency of oscillation of a positive-grid oscillator, it is usually. assumed that the space charge effect is negligible. Under this assumption, the potential distribution in the space between the plane-parallel electrodes is linear. Thus the electric field in the space is uniform and the average velocity of electron flight can be used to evaluate the frequency of oscillation. The presence of space charge affects the potential distribution in space so that the electric field in this region is no more constant. Hence more exact formula must be used to compute the frequency of oscillation. The calculation is further complicated by the fact that the anode potential is usually made slightly negative with respect to the cathode. In this case, the location of the virtual cathode at which the electrons turn back does not coincide with that if a straight line potential distribution were assumed. The predicated frequency of oscillation is about 10-20 percent lower than that if space charge were neglected.
1946, 6(2): 86-99.
doi: 10.7498/aps.6.86
摘要:
本文先論一實變數之線形微分演素（operator)之若干性質，主旨在尋求Hermite 演素之條件，並舉出量子力學中之各種例證。
本文先論一實變數之線形微分演素（operator)之若干性質，主旨在尋求Hermite 演素之條件，並舉出量子力學中之各種例證。
1946, 6(2): 108-111.
doi: 10.7498/aps.6.108
摘要:
本文叙述某些元素之同位素之數目，可由其原子序數及其所在之週期之關係以求德之。設Z為一元素之原子序數，N.為其所在週期内所含元素之實在種數，若Zlv/2N之値恰為一整數時，則此整數印表示此元素之同位素之個數。由第一週期至第六週期，有十五種元素可適用於本情形。計算値與實際觀察値相比較，約有十種元素符合；而在四，五兩週期内之元素，更完全符合。
本文叙述某些元素之同位素之數目，可由其原子序數及其所在之週期之關係以求德之。設Z為一元素之原子序數，N.為其所在週期内所含元素之實在種數，若Zlv/2N之値恰為一整數時，則此整數印表示此元素之同位素之個數。由第一週期至第六週期，有十五種元素可適用於本情形。計算値與實際觀察値相比較，約有十種元素符合；而在四，五兩週期内之元素，更完全符合。
