Pool Boiling on Wire in Microgravity - What Have We Learned

In the past years, steady pool boiling of degassed R113 on thin platinum wires has been studied systematically in our lab, including experiments in long-term microgravity aboard RS-22, in short-term microgravity in the Drop Tower Beijing / NMLC, and in normal gravity on the ground. Slight enhancement of nucleate boiling heat transfer is observed in microgravity, while dramatic changes of bubble behaviors are much evident. The value of CHF in microgravity is lower than that in normal gravity, but it can be predicted well by the Lienhard-Dhir correlation, although the dimensionless radius in the present case is far beyond its initial application range. The scaling of CHF with gravity is thus much different from the traditional viewpoint. Considering the influence of the Marangoni effects, the different characteristics of bubble behaviors in microgravity have been explained. A new bubble departure model has also been proposed, which can predict the whole observation both in microgravity and in normal gravity.

HIRFL-CSR频谱现象：中心频率突变分析研究

In commissioning the HIRFL-CSR (Cooler Storage Ring of Heavy Ion Research Facility in Lanzhou),with the spectrum analyzer monitoring the beams on-line, we measured many parameters of the beam status for improving quality of the heavy ion beams. In this paper, the sudden change of the beam center frequency is analyzed.A theoretical analysis is done mainly on instabilities of the electron voltage and the neutralization factor. Simulations were made for the problem. According to the simulation result, we can conclude that it is the instability of neutralization factor that caused the problem. 中文摘要：HIRFL-CSR调试过程中，利用频谱分析仪实时监测束流，根据其上测的数据进行相关参数调整，改善束流的品质。本文对分析仪上观测到的现象一束流的中心频率发生突变进行了研究，主要就电子束的高压不稳定性和中性化因子的突变做了理论分析，并进行了相关的模拟计算 ，根据模拟结果初步断定该现象的出现由电子束的中性化因子导致。

C离子束诱变产生甜高粱汁酒精酵母高产菌株的研究

利用100MeV/uC离子束对高产酒精酵母菌株进行了辐照诱变的研究。采用红四氮唑作为筛选指示剂,得到了5株产酒能力有所提高的突变酵母菌。利用甜高粱汁的发酵结果表明,T4突变菌株的产酒精能力比原始出发菌株提高了18.6%,且发酵液中的残糖含量也有所降低。随后对T4菌株在甜高粱汁中的最适宜发酵条件做了初步探索,结果表明:最适发酵温度和pH值分别为30℃和4.5。通过10l发酵罐的验证试验表明:在同样发酵条件下,T4菌株的发酵率和产酒精能力都比原始出发菌株提高了12%。

HIRFL-CSR频谱现象:中心频率突变分析研究

HIRFL-CSR调试过程中,利用频谱分析仪实时监测束流,根据其上测的数据进行相关参数调整,改善束流的品质。本文对分析仪上观测到的现象—束流的中心频率发生突变进行了研究,主要就电子束的高压不稳定性和中性化因子的突变做了理论分析,并进行了相关的模拟计算,根据模拟结果初步断定该现象的出现由电子束的中性化因子导致。