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1.
Error field caused by non-coaxiality among poloidal and toroidalfield coils on HL-2M tokamak is calculated with SURFMN and SURFMN_TFCOIL code. According to the coil installation error chosen by international tokamak and the installation experience of HL-2A tokamak, the maximum shift distance of poloidal- and toroidal-field coils on HL-2M tokamak is chosen 3~8mm, and the maximum tilt angle of that is 0.05~0.1 degree. The probability density and accumulative probability of error field are calculated with the maximum shift distance 3mm, 5mm and 8mm respectively, and the maximum tilt angle 0.05, 0.075 and 0.1 degree respectively. The results show that: (1) the probability density distribution become flat and the range of error field B3-mode/BT is enlarged significantly with the increase of maximum shift distance of field coils; (2) the shift of poloidal- and toroidal-field coils influences error field more heavily than tilt does; (3) when the shift of poloidal- and toroidal-field coils reaches 5mm, especially 8mm, the error field is more possibly reach 2×10-4.  相似文献   

2.
微小等离子体反应器的导出机理研究   总被引:1,自引:0,他引:1  
An extraction mechanism based on micronozzle in the bottom of the microhollow cathode and applied bias electrical field is proposed, and digitally simulated with a two dimensional fluid model. When the operating gas is SF6 and its pressure is 2~9kPa, radius of the micronozzle is 0.25μm, maximum F atom flux density is between (1.53~5.62)×1014cm-3·s-1, maximum SF5+ flux density is between (2.46~7.83)×1016cm-3·s-1. When gas pressur is  5kPa,average energy of F atom at sample surface is 3.82eV, dispersion angle is −14º~14º; average energy of SF is 25eV, dispersion angle is −13º~14º. When applied voltage across hollow cathode and sample is between 10~50V (sample as cathode), average energy of SF is between 52~58eV. The density of F and SF in the simulation result could satisfy the requirement for silicon etching, and the feasibility of scanning plasma etching validated.  相似文献   

3.
The principle and experimental results of the open microwave resonant cavity measurement system were introduced. The models were steel ball models and the ball models coated with copper. The diameter of the models was 10mm. The models were launched in ballistic range. The model velocity was 5.44 km.s-1. The wake electron density of the models was obtained. The experimental results presents that the response time of the open microwave resonant cavity measurement system was quicker than 1ms. The results showed the wake electron density ranged from 109cm-3 to 1011cm-3 could be achieved.  相似文献   

4.
�����п�ʽ΢��г��ǻ����ϵͳ�о�   总被引:1,自引:1,他引:0       下载免费PDF全文
介绍了开式微波谐振腔测量系统的工作原理及试验结果,获得了Æ10mm钢球模型在6.65kPa干燥空气中以速度5.44km.s-1飞行时的尾迹电子密度测量结果,并且与国外弹道靶试验数据进行了比较。试验结果表明,该系统能够满足模型尾迹电子密度变化对测量系统响应时间的要求,能很好地反映尾迹电子密度变化细节,电子密度测量范围达到109~1011cm-3。  相似文献   

5.
用SURFMN和SURFMN_TFCOIL代码计算了由HL-2M装置磁场线圈安装误差产生的误差场。根据国外托克马克装置TF和PF线圈安装误差的取值范围,以及HL-2A装置安装的经验,计算选取的TF线圈和PF线圈最大位移范围为3~8mm,最大倾斜角度为0.05~0.1°。选取9组数据计算了误差场的概率密度分布和累计概率分布。结果发现:在TF和PF线圈安装误差取值范围内,随磁场线圈最大移位增大概率密度显著变平,误差场B3-mode/BT的分布范围显著增大;磁场线圈的位移比倾斜对误差场的影响更大;当磁场线圈最大位移达到5mm时误差场大于2×10-4的概率都比较大,特别是线圈最大位移等于8mm时,误差场大于2×10-4的概率在60%以上。  相似文献   

6.
介绍了一种低功率圆柱形阳极层离子源的工作特性和束流分布特性。离子源正常工作参数范围为工作电压200~1200V,放电电流0.1~1.4A,工作气压1.9×10-2~1.7×10-1Pa,气体流量5~20sccm。离子源有两个工作状态:发散状态和准直性状态。  相似文献   

7.
HL-2A装置SDD软X射线能谱测量结果   总被引:1,自引:1,他引:0  
Measurements of soft X-ray spectra during Electron Cyclotron Resonance Heating (ECRH) has been achieved on HL-2A tokamak using two independent silicon drift detector (SDD) systems. Electron temperatures are derived from the measured soft X-ray energy spectra. A comparison indicates that the results measured by SDD are consistent with ECE measurements. Experimental results of soft X-ray spectra measure- ment using SDD show that the increment of electron temperature is larger at z=0 than that at z = 16.4cm chord, so, we can conclude that the energy of ECW is deposited dominantly in the core of plasma and electron temperature profile become peaked during on-axis ECRH (BT=2.4T). The statistic survey of ECRH discharges (2.41T ≤BT≤2.43T,1.5×1019m-3ne≤2.5≤1019m-3,300kW≤ECRH power≤600kW) shows that plasma electron temperature rises obviously during on-axis ECRH, especially, in the core of plasma (z=0). It has been observed that the on-axis ECRH can make electron temperature increase up to 30%~80% at z=0 chord and 15%~55% at z=-16.4cm chord.  相似文献   

8.
研究了在托卡马克装置中中性束注入时快离子自举电流的产生。利用快离子分布函数在两小增量δ=ρp/a (ρp是极向拉莫尔半径,a是小半径)和δ*=τB/τs(τB是俘获粒子反弹周期,τs是慢化时间)下进行展开的方法求解漂移动力学方程;给出了快离子自举电流的一般表达式。计算了圆截面大纵横比托卡马克中快离子自举电流密度分布和总的快离子自举电流的大小,研究表明:在中性束垂直注入时快离子自举电流约占总电流10%;自举电流的大小既敏感地依赖于中性束注入的角度——平行注入时较小、接近垂直时迅速增大,同时也较强的依赖于快离子的产生速度与临界速度的比值,即vb/vc,而vb2∝E(束能量);自举电流的大小随注入束能量的增加而迅速增大。  相似文献   

9.
We describe a simple method to measure the top quark mass in the channel that may be useful in Run II of D? detector. The method is validated by applying it to the Run Ib data.  相似文献   

10.
We examine the Wilson confining-area behavior for QCD(SU( )) as described by a Witten effective reduced dynamics of constant-gauge fields. We show the model to be exactly soluble when dynamical quark fields are added, together with fermion asymptotic freedom behavior. Additionally, we give arguments for the triviality of the chiral-SU(N) non-abelian Thirring model at the t′Hooft limit of large number of colors in the context of these constant-gauge-field reduced dynamics. Received: 26 May 2004, Revised: 16 June 2005, Published online: 30 August 2005  相似文献   

11.
报道了BSA-SDS-Ag聚合物纳米微粒的制备及水凝胶的性质,用X射线衍射(XRD)、透射电镜(TEM)、傅里叶变换红外(FT-IR)光谱考察了这种聚合物微粒的结构,微粒粒径32nm左右,用UV/Vis光谱及SEM考察了冰凝胶的性,表明Ag^ 离子先与BSA产生化学键合,再学原了Ag粒,进行聚合成网状结构的聚合物。  相似文献   

12.
Abstract

Fourier transform infrared spectroscopy has been used to study quantitatively the acetylation of monodisperse polystyrene microspheres with diameters ranging from 7 to 9μm. The CH2 stretching infrared vibration mode at 2921 cm?1 was used as the internal intensity standard. The acetylation extent could be easily measured by comparing the relative intensities of the bands of acetyl group (1678, 1415, 1359 cm?1) or the bands due to the para-substituted benzene ring to the band at 2921 cm?1 from the calibration curve.  相似文献   

13.
14.
 在采用体积相加原理计算混合物物态方程的基础上,建立了一种物理模型确定混合物温度。根据混合物中各组分温度和压强平衡条件,采用压强-密度迭代方法计算给出混合物物态方程,编制了两种组分的混合物物态方程计算程序。为检验建立的温度模型的合理性及程序的有效性,分析了不同密度、温度状态的氢(H2)和钨(W)组成的混合物状态参量,计算了以下情形及其组合情形的混合物物态方程:H2和W以不同质量比混合;质量比固定,单组分状态不同;温度区间和密度区间不同。研究表明:实际应用中在建立的混合物温度模型基础上确定的混合物物态方程是合理的。  相似文献   

15.
傅里叶望远镜外场实验性能改进和结果分析   总被引:4,自引:0,他引:4  
为了实现对傅里叶望远镜成像系统更接近实际的仿真,改进了外场实验系统结构。采用反射式目标,利用准直扩束镜替代空间滤波器和准直透镜,使用大靶面电荷耦合器件作为监视器。在无大气和包含200m水平大气两种情况下,分别对2.5mm的4种不同空间频谱分布目标进行实验。实验选用9×9,17×17,33×33和65×65傅里叶分量分别进行重构。最高成像角分辨率为3.5″。结果表明含大气与无大气重构结果的Strehl比值相近,从而证明傅里叶望远镜成像系统能够克服下行链路低阶大气扰动的影响。  相似文献   

16.
Using time-resolved high-speed shadowgraphy, the dynamics of phenomena due to laser-based lithotripsy is studied. Collapsing mechanism of bubble formed therein is investigated. In order to study the mechanism, the optically implemented mathematical morphology is applied. The study of the shape of the plasma and the collapsing region of the bubble of fluid that we are studying can possibly be used for practical application for laser-based lithotripsy.  相似文献   

17.
T. S. Lebedev 《高压研究》2013,33(1-6):720-722
Abstract

Results of petrophysical PT-experiments are discussed. Used is a method of program modeling of experiments. Thermobaric dependence of elastic properties of acid, intermediate and basic rocks as well as elastic wave velocity anisotropy in amphibolites is studied. Deep PT-regimes effect on electrical resistance of dry and water-saturated rocks has been studied. PT-conditions of full loss of the remanent magnetization of volcanites have been established. A number of regional petrophysical lithosphere models has been constructed.  相似文献   

18.
分子费米共振拉曼光谱强度分析   总被引:2,自引:0,他引:2  
测量了CCl4和CS2分子的Raman光谱。用Bertran理论和群论等相关理论对其光谱强度进行了分析,获得了发生费米共振分子的拉曼光谱强度的特殊规律: (1)发生费米共振的基频和倍频(和频)间发生能量转移,两光谱强度大小相互接近,当发生费米共振的基频和倍频(和频)间距离很小时,两发生费米共振的光谱强度相等(R=1);(2)能出现倍频光谱强度高于其基频光谱强度;(3)也会观测到费米共振光谱,而观测不到参与费米共振的和频中的基频光谱。此研究对化学、材料科学中的分子结构、材料成分等研究中的谱线认证、归属有很好的参考价值。  相似文献   

19.
吴惠彬  梅凤翔 《中国物理 B》2010,19(3):30303-030303
This paper studies the symmetry of Lagrangians of nonholonomic systems of non-Chetaev's type. First, the definition and the criterion of the symmetry of the system are given. Secondly, it obtains the condition under which there exists a conserved quantity and the form of the conserved quantity. Finally, an example is shown to illustrate the application of the result.  相似文献   

20.
Simulated contours of self-reversed lines of Tl at 535 nm (72S1/2−62P3/2) and 378 nm (72S1/2-62P1/2) in alternating-current closed-arc radiation in mercury vapor with an addition of Tll were compared with experimental contours. It is shown that while a single self-reversed contour has many different sets of model parameters that ensure coincidence of experimental and calculated profiles, in the case of operation with a large data file of contours that correspond to different directions of observation along chords perpendicular to the discharge axis, and with different lines that have a common level, such a set of parameters becomes virtually unique. Instantaneous spatial distributions of Hg and Tl atoms in the ground state and of Tl atoms in the 62P3/2 state are determined and the parameters of the van der Waals broadening of the 72S1/2 level are found. It is shown that a considerable “red” shift of absorption contours in the outer layers of the discharge is observed. The results obtained contradict the presumed existence of local thermodynamic equilibrium in the given discharge. Reported at the Conference “Plasma Physics and Plasma Technologies,” Minsk, September 15–19, 1997 Petrozavodsk State University, 33, Lenin Ave, Petrozavodsk, 185640, Russia. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 65, No. 5, pp. 761–768, September–October, 1998.  相似文献   

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