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11.
混合/掺杂团簇研究进展 总被引:3,自引:0,他引:3
本文系统地评述了混合/掺杂团簇的研究现状及其在近十余年来取得的重要进展,着重讨论各类混合/掺杂团簇体系的电子结构和几何结构特点。同时,论述了混合/掺杂团簇的研究背景,概述了混合/掺杂团簇发生装置的研制进展及其特色,提出了若干有待进一步研究的问题。 相似文献
12.
The first results of divertor discharge and supersonic molecular beam injection on the HL-2A tokamak 总被引:1,自引:0,他引:1 下载免费PDF全文
HL-2A tokamak is the first tokamak with divertors in China. The
plasma boundary and the position of the striking point on the target
plates of the HL-2A closed divertor were simulated by the current
filament code and they were in agreement with the diagnostic results
in the divertor. Supersonic molecular beam injection (SMBI) system
was first installed and tested on the HL-2A tokamak in 2004. In the
present experiment low pressure SMBI fuelling on the HL-2A closed
divertor was carried out. The experimental results indicate that the
divertor was operated in the `linear regime' and during the period of
SMB pulse injection into the HL-2A plasma the power density convected
at the target plate surfaces was 0.4 times of that before or after
the beam injection. It is a useful fuelling method for decreasing the
heat load on the neutralizer plates of the divertor. 相似文献
13.
肖维文 邹晓岚 丁玄同 董家齐 刘泽田 宋绍栋 高亚东 姚良骅 冯北滨 宋显明 陈程远 孙红娟 李永高 杨青巍 严龙文 刘仪 段旭如 潘传红 刘永 《中国物理快报》2009,26(3):159-162
A broadband, O-mode sweeping Doppler reflectometry designed for measuring plasma E×B flow velocity profiles is operated in HL-2A. The main feature of the Doppler reflectometry is its capability to be tuned to any selected frequency in total waveband from 26-40 GHz. This property enables us to probe several plasma layers within a short time interval during a discharge, permitting the characterization of the radial distribution of plasma fluctuations. The system allows us to extract important information about the velocity change layer, namely its spatial localization. In purely Ohmic discharge a change of the E×B flow velocity profiles has been observed in the region for 28 〈 r 〈 30cm if only the line average density exceeds 2.2×10^19 m^-3. The density gradient change is measured in the same region, too. 相似文献
14.
报道了HL-2A装置最新的实验结果,讨论并研究了超声分子束的注入位置对分子束在等离子体中的消融和穿透的影响,其中包括电离后的分子束粒子在磁场梯度作用和 E × B 漂移下的加速或减速及由此形成的冷通道效应.研究结果表明,磁场梯度和 E × B 漂移对于超声分子束的加料效果、消融和穿透有着重要的作用.强场侧注入可使电离后的电子和离子更深地进入等离子体芯部.这些研究对于更好地理解超声分子束与等离子体的相互作用和优化设计加料系统有一定作用. 相似文献
15.
Effect of laser spot size on fusion neutron yield in laser--deuterium cluster interactions 下载免费PDF全文
The effect of the laser spot size on the neutron yield of table-top nuclear fusion from explosions of a femtosecond intense laser pulse heated deuterium clusters is investigated by using a simplified model, in which the cluster size distribution and the energy attenuation of the laser as it propagates through the cluster jet are taken into account. It has been found that there exists a proper laser spot size for the maximum fusion neutron yield for a given laser pulse and a specific deuterium gas cluster jet. The proper spot size, which is dependent on the laser parameters and the cluster jet parameters, has been calculated and compared with the available experimental data. A reasonable agreement between the calculated results and the published experimental results is found. 相似文献
16.
Noble gases (argon, krypton, and xenon) are puffed into vacuum through a nozzle to produce clusters for studying laser-cluster interactions. Good estimates of the average size of the argon, krypton and xenon clusters are made by carrying out a series of Rayleigh scattering experiments. In the experiments, we have found that the scattered signal intensity varied greatly with the opening area of the pulsed valve. A new method is put forward to choose the appropriate scattered signal and measure the size of Kr cluster. 相似文献
17.
利用具有定向速度的超声分子束注入技术,研究了HL-2A装置在较低加热功率条件下实现L-H转换的等离子体放电特征,从边缘密度分布的差异比较分析了普通送气和超声分子束注入对L-H转换的影响.实验结果表明,HL-2A装置上采用超声分子束注入可直接触发L-H转换,明显降低L-H转换功率.通过对大量实验数据的分析和整理发现,利用超声分子束注入实现L-H转换的最低加热功率,比同等条件下采用普通送气实现L-H转换的最低加热功率减少约10%. 相似文献
18.
用原子簇RhBSi25模拟含四面体间隙位Rh和替代位B构成的络合物的硅晶体,采用量子化学中Xα-SW分子轨道理论计算体系的电子结构,电荷分布分析表明,此体系不能用通常的离子模型来描述。 相似文献
19.
用22道Hα辐射测量阵列观测了HL-2A装置偏滤器位形超声分子束的注入过程。观测结果表明:在HL-2A装置偏滤器位形下,当分子束注入气源压强大于1MPa时,Hα辐射沿径向分布存在两个峰值,其第二个Ha辐射峰值位于r/a~0.8附近,表明大部分氢粒子在等离子体边缘(SOL区域)即被离解或电离,但仍有部分氢粒子沉积在分界面内5cm。 相似文献
20.
High-energy ion emission from intense-ultrashort (30 fs) laser-pulse-cooled deuterium-cluster (8OK) interaction is measured. The deuterium ions have an average energy 20 keV, which greatly exceeds Zweiback‘s expectation[Phys. Rev. Lett. 84 (2000) 2634]. These fast deuterium ions can be used to drive fusion and have a broad prospect. 相似文献