GAME-TIBET青藏高原云和降水综合观测概况及初步结果

对中日合作青藏高原能量水分循环试验（ Ｇ Ａ Ｍ Ｅ Ｔ Ｉ Ｂ Ｅ Ｔ） 项目中云和降水的多普勒雷达观测使用的气象观测仪器和获取的资料等情况进行了扼要的总结，并给出了那曲地区降水的日变化、不同雨量计测量降水的对比分析、风速对测量降水影响、多普勒雷达资料的个例分析及云的数值模拟等初步结果。

MHD Instabilities and Their Effects on Plasma Confinement in Large Helical Device Plasmas with Intense Neutral Beam Injection

MHD stability of the Large Helical Device (LHD) plasmas produced with intenseneutral beam injection is experimentally studied. When the steep pressure gradient near the edge isproduced through L-H transition or linear density ramp experiment, interchange-like MHD modes whoserational surface is located very close to the last closed flux surface are strongly excited in acertain discharge condition and affect the plasma transport appreciably. In NBI-heated plasmasproduced at low toroidal field, various Alfven eigenmodes are often excited. Bursting toroidalAlfven egenmodes excited by the presence of energetic ions induce appreciable amount of energeticion loss, but also trigger the formation of internal and edge transport barriers.

锻造钢锭中缩松形成的临界条件

钢锭“A”型偏析区和“V”型偏析区中所呈现的缩松,主要受着钢锭形状,尺寸以及化学组成等因素的影响。为了获得完整的钢锭,在调查3～220t钢锭以及计算机算出的凝固状态的基础上,研究了缩松形成的临界条件。结果发现,当水平方向上ε·R^(1.1)小于临界值时,将在“A”型偏析区中产生缩松;而当垂直方向G小于临界值时,将在“V”型偏析区中产生缩松,此处ε为冷却速度,R为凝固速度,G为温度梯度。同时还发现,临界值随着固—液共存的温度范围δ的加大而提高,也就是说更易于形成缩松。

锻造钢锭中“A”型偏析形成的临界条件

“A”型偏析的形成,主要受到钢锭的尺寸和化学成分等因素的影响,因此,在对9～400t商品钢锭中通过计算机算出来的凝固状态和重量为14kg的试验钢锭进行统计的基础上,研究了“A”型偏析形成的临界条件。结果发现,当在水平方向上ε·R^(1.1)小于临界条件时,就将形成“A”型偏析,临界值随着δ的增加而增大,其中ε、R和δ分别为冷却速度、凝固速度和固—液共存的温度范围。同时还发现,即使在δ相同的情况下,临界的ε·R^(1.1)值也将随着化学成分的变动而变化,这一临界值按照普通碳钢、含Cr钢、含Ni钢的顺序而渐次递减,而低Si钢则是最低的。考虑到钢锭化学成分的全部影响,“A”型偏析形成的临界条件可以完整地通过ε·R^(1.1),以及溶质富集钢液与基体钢液之间的比重差来表示。

High Density Plasma Heating by EC-Waves Injected from the High-Field Side for Mode Conversion to Electron Bernstein Waves in LHD

To realize an excitation of electron Bernstein waves （EBW） via mode conversion from X-mode waves injected from the high magnetic field side （HFS）, new inner-vessel mirrors were installed close to a helicM coil in the large helicM device （LHD）. 77 GHz electron cyclotron （EC） wave beams injected from an existing EC-wave injection system toward the new mirror are reflected on the mirror so that the beams are injected to plasmas from HFS. Evident increases in the electron temperature at the plasma core region and the plasma stored energy were observed by the HFS beam injection to the plasmas with the line-average electron density of 7.5~ 1019 m-3, which is slightly higher than the plasma cut-off density of 77 GHz EC-waves, 7.35~ 1019 m-3. The heating efficiency evaluated from the changes in the time derivative of the plasma stored energy reached ,,~70%. Although so far it is not clear which is the main cause of the heating effect, the mode-converted EBW or the X-mode wave itself injected from the HFS, an effective heating of high-density plasma over the plasma cut-off of EC-wave was successfully demonstrated.

Pellet Injectors Developed at the Pelin Laboratory for Steady-State Plasma Fuelling

Pneumatic and centrifugal injectors for steady-state plasma refuelling bysolid hydrogen, deuterium and tritium pellets have been designed at the PELIN Laboratory to meetrequirements of LHD, TORE SUPRA, and ITER. Presented here is a review of these injectors' designsand results.

Refueling for Steady-State Plasma by Repetitive Pellet Injection in Large Helical Device

A repetitive pellet injector has been developed for investigation ofrefueling issues towards the steady-state operation in Large Helical Device (LHD). Continuousoperation of more than 10000 pellet launching at 10 Hz has been demonstrated. The maximum repeatingrate is 11 Hz. No technical constraint for longer operation has been found. The reliability ofpellet launch has exceeded 99.9%. The initial application to the NBI-heated plasmas has beensuccessful in the last experimental campaign of LHD. Although the pulse length is limited by theoperational constraint of NBI, the plasma with a density of 8 X 10^(19) m^(-3) has been sustainedfor 2 s by the pellet injection at 10 Hz. A prospect for the future experiment is discussed on thebasis of the initial result.

高硬度EPDM胶料

1、简介三元乙丙橡胶(EPDM)因具有低饱和度而不能象二烯类橡胶那样通过添加大量硫黄来使其获得高硬度,其它途径如与反应型酚醛树脂或聚烯烃并用虽然也能获得高硬度胶料,但其混炼胶加工性能低劣,其硫化胶的机械性也欠佳。本文作者通过EPDM与液状二烯烃并用,且加入大量硫黄开发出了一种具有优异的加工性能和硫化胶性能的高硬度胶料。此外。