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1.
1.06μm激光辐照金盘靶的软X光转换   总被引:1,自引:1,他引:0  
在1.06μm激光辐照金盘靶实验中,利用坪响应X光二级管探测器测量了软X光能量(0.1-1.5keV)角分布,得到了软X光转换效率。实验条件:激光波长λL=1.06μm,EL=60-500J,τpm≈800ps,f/1.7,IL=10^1^3-10^1^4W/cm^2。实验结果表明:软X光能量角分粗略呈α+bcosθ分布,软X光转换效率随激光强度的增加而降低。当靶面激光焦斑直径235μm,激光强度  相似文献   

2.
用光谱学方法研究不同放电等离子体粒子约束   总被引:2,自引:2,他引:0  
本文用光谱学方法研究在HL-1装置上LHCD及ECRH等离子体,弹丸注入等离子体,偏压电极与偏压孔栏等离子体粒子约束特性。结果表明:在弹丸注入使用正向偏压电极与偏压孔栏期间,等离子体粒子约束行到改善,较低密度下(^ne<2.0×10^1^3cm^-^3),LHCD脉冲期间粒子约束得到改善;而当密度^-ne大于2.0×10^1^3cm^-^3时,等离子体约束变坏。ECRH脉冲期间粒子约束得不到改善。  相似文献   

3.
本文给出了发射探针和电容探针测量等离子体电位的实验和方法。发射探针采用直流功率加热,并在较强电子发射条件下运行(I_(e0)/I_(e0)>1)。电容探针表面二次电子发射系数δ≥1。本文对发射探针的电子发射性能、工作电流、电容探针的输入、输出电压关系进行了标定实验。得到了电容探针的校准系数分别为3×10(-3)、5×10(-4)。实验给出了MM-4会切中心等离子体电位V_(p4)=-82±9-122±12V;MM-4U东、西会切中心等离子体电位分别为V_(P4u1)=-52.9±3.2V,V_(P4u2)=-62±3.2V。  相似文献   

4.
制备了四氯四铜酸苯铵盐(C6H5NH3)2CuCl4单晶,Mr=187.26,由四园衍射数据确定了晶体结构,晶体属单斜晶系,空间群P21/a,a=0.7184(1),b=0.7448(2),c=1.5070(4)nm,β=100.67(2)°,V=0.7924nm^3,Z=2,Dx=1.650gcm^-3,(Mo,Ka)=0.071069nm,μ=4.056mm^-1,F(000)=389,R=0  相似文献   

5.
HL—1M多发弹丸加料等离子体的特性   总被引:5,自引:0,他引:5  
对HL-1M装置在一次放电中注入3-8粒氢弹丸的欧姆加热等离子体密度分布和扰动特征进行了研究。实验表明,器壁再循环对高密度的获得有重要的影响。在再循环较高的条件下连续注入3粒1.0mm弹丸,获得了加料实验的最好参数:等离子体中心密度ne(0)=5.3×1013cm-3,总体储能Wp=6.0kJ,τe=26ms。用CCD相机拍摄了弹丸消融云的照片,并对消融过程进行了简要的分析。结果证实,消融的不对称和弹丸轨迹的偏转是电子侧消融强于离子侧的结果,弹丸发射间隙及完整性对密度扰动有重要的影响。  相似文献   

6.
在成功制备C60外延薄膜的基础上,我们又尝试了碱金属Rb对该膜的掺杂。结果表明,从室温至80K左右,Rb3C60薄膜的电阻温度系数大于0,并近似符合公式:ρ(T)=a+bT^2,与单晶样品一致。但是,当温度低于80K以后,出现了弱的对数局域。在5K、零场下,样品的Jc值一般为10^3-10^4A/cm^2,且有如下规律:Jc(T)=Jc(0)(1-T/Tc)^a,α=1.3-2.0。此外,我们还测  相似文献   

7.
HL—1M装置多发弹丸加料实验观测   总被引:9,自引:2,他引:7  
首次在HL-1M装置上投放使用的多发弹丸加料系统,能一次注入多达4粒Φ1.0mm的氢弹丸,弹丸速度在500-800m.s^-1之间。弹丸注入后,得到离子体密度峰化系数nc(0)/〈nc〉=1.8能量约束时间与喷气加料放电的相比提高30%以上的实验结果。观察到了弹丸注入等离子体引起弹丸消融物沿磁力线流动的图像变化,电子温度分布和MHD行为的演变过程以及新的边缘等离子体特性。  相似文献   

8.
对于La0.2Ba0.8-xCax(O,CO3)其中x=0.0、0.2、0.4、0.6氧化物在973K及甲烷氧化偶联(OCM)条件下,无Ca^2+的样品可用表面BaCO3和(LaO)2CO3的Raman谱及810cm^-1附近的O2^2-特征峰来表征;含Ca^2+的样品,则表现了混合碳酸盐(Ca,Ba)CO3的特征,还有位于1135cm^-1(w)和810cm^-1(w)的O2^-、O2^2-瞬时  相似文献   

9.
分光光度法测定饮料食品中痕量有机锗和无机锗的研究   总被引:6,自引:1,他引:5  
本文研究了在溴化十六烷基三甲基铵(CTMAB)抗坏血酸(Vc)存在下,苯基荧光酮(Pf)光度法测定痕量锗的最佳实验条件及配合物的组成,从而建立了测定痕是锗的新方法,其方法的灵敏度ε=1.034×10^5L.mol^-1.cm^-1锗含量在0-16.8μg/25mL范围内符合比耳定律,稳定性好,操作简便,快速。应用本法测定了矿泉水,茉莉花茶,大蒜中有机锗和无机锗的含量,回收率在91.6%-103.5  相似文献   

10.
用线偏振的脉冲激光泵浦的Sr(5p^1P1,M=0)原子,在束气条件下,与Ar原子碰撞而发生P轨道角动量的跃迁。在不同的氢气压力下,通过检测Sr原子荧光在水平和垂直方向上的偏振分量随时间的变化,确定了去偏振速率常数kp=2.5±0.5×10^-9cm^3mol^-1s^-1。由此推导出角动量碰撞跃迁的截面为σT=2nm^22,如此之大的跃迁截面归结为Sr(5p^1P1)和Ar之间的长程相互作用。  相似文献   

11.
小功率等离子体射流的流特性   总被引:3,自引:0,他引:3  
采用焓探针对小功率(5kW)热喷涂等离子体射流的焓、温度和速度进行了测量和计算。研究了气体成分、流量、电弧电压和电流对等离子流体的焓、温度和速度分布的影响。结果表明,对于单一氩气等离子体,当使用新喷嘴时,增大氩气流量能够使喷嘴内部电弧弧根向出口方向移动,从而增加等离子体射流的焓、温度和速度。对于Ar-N2等离子体,增加气体中氮气的含量,会提高等离子电弧电压,在同样的输入功率下,改变等离子电流和电压对等离子体的焓、温度和速度影响较小。对于Ar-N2等离子体,增加氢气含量会明显地提高等离子射流的速度和热传递。  相似文献   

12.
设计和制造了适合工业应用的强流金属离子源。离子源的电弧阴、阳电极之间和放电室壁采用永磁体阵列形成导流、屏蔽磁场,改进了电弧的放电特性和提高等离子体密度。离子注入源在加速电压为30kV、50 Hz 条件时,平均束流流强约为30mA,调试结果表明附加磁场提高了离子源性能。  相似文献   

13.
The propagation of plasma jets with argon gas is characterized in terms of two factors, the effect of electric field distribution along the tube and the effect of voltage polarity, from the observed results of optical signals along the entire column of plasma. The optical signal of plasma propagates from the high electric-field region of high-voltage electrode toward the low field region of the open air-space, regardless of the polarity of the voltage. The optical intensity and the propagation velocity are higher for the positive voltage than for the negative voltage. Moreover, the length of plasma plume exited from the end of the glass tube into the open air is shorter for the negative voltage. When the optical intensity is strong enough, a secondary peak signal follows the primary peak. In the plasma column on the inside of the glass tube, the optical intensity and the propagation velocity depend on the strength of the electric field; they are both high at the high-field region of voltage terminal and decay toward the end of the tube. The velocity is as fast as 104 m/s at the high-field region and slows down to 103 m/s at the low-field region of the glass-tube end. However, the plasma accelerates drastically to be (104–105) m/s after exiting the glass tube toward open air, even though the electric field is a quite low and thus the optical signal decays low before fading out. The experimental observations present in this report are explained with the propagation of the plasma diffusion waves.  相似文献   

14.
Techniques from complexity and criticality theory have fruitful applications to a wide range of natural and laboratory plasma systems. Here we review examples that have direct observational relevance, spanning fusion, the Earth's magnetosphere, the sun and astrophysical accretion disks. The complex systems techniques range from sandpiles to a novel loop-based dynamical model, together with modern approaches to model-independent data analysis.  相似文献   

15.
常压窄间隙介质阻挡放电等离子体辐射特性   总被引:1,自引:0,他引:1  
利用带有透明电极与可测向观察的一个介质阻挡放电(DBD)实验装置对它的常压窄间隙等离子体辐射特性进行了实验研究。结果表明:这一DBD装置的辐射特性会受激励电压、激励频率、DBD结构等多种因素影响。在频率为10~20kHz高压电源激励下,采用窄间隙、薄电介质层结构DBD可以大幅度提高放电空间的电场强度,增加放电功率密度,提高了放电装置性能。  相似文献   

16.
为深入认识空间约束增强的物理机理,采用二维可压缩流体模型,建立平板约束下激光诱导等离子体动力学行为的数值模拟模型,计算了平板约束下等离子体的演化过程,得到的一系列时间分辨的温度分布结果与实验结果基本一致.揭示了平板约束下,反射激波对等离子体的压缩作用导致等离子体温度升高的机理.对不同激光能量和不同约束板间距对等离子体温度增强效果和增强时刻的影响进行了研究,两板间距增加,增强时刻明显延迟,等离子体温度的增强效果削弱.  相似文献   

17.
Summary In this paper we formualte a master equation approach describing a D+T thermonuclear plasma in a lumped phase space. From the first moments of this master equation and performing the pass to the continuous limit the evolution equations for the expected phase space ion densities emerge. Also we have obtained the evolution equations of the equal time correlation and covariance functions. Finally we have deduced the hydrodynamic equations that arise from a master equation approach.  相似文献   

18.
Summary The present paper describes a direct method of obtaining are expression of the distribution function of charged particles which diffuse in a plasma. The distribution function in velocity, angle and time is presented starting from the Fokker-Planck equation. Temperature, average velocity and energy of charged particles (electron or ions) have also been calculated as functions of time. The authors of this paper have agreed to not receive the proofs for correction.  相似文献   

19.
Summary A microwave coherent backscattering experiment has been carried out on Mirabelle, a weakly ionised plasma device, with the objective of measuring the electron density fluctuation level. The experiment is a preliminary step in order to prepare the detection system for a microwave stimulated backscattering experiment. The incident electromagnetic wave is focused in front of a plane grid which excites ion acoustic or electron Bernstein waves inducing fluctuations in the plasma. The backscattering signal is collected by the launching circuit and detected by homodyne mixing. The typical ratio of the scattered power to the incident power is about 10−12 and the relative density fluctuations are of the order of δn e/n e=10−3 against a background electron density ofn e=1–5·109 cm−3. The backscattering measurement is compared with Langmuir probe measurements. The spectral width of the backscattered signal has also been studied, by taking into account effects due to the incident wave focusing and plasma wave damping. The authors of this paper have agreed to not receive the proofs for correction  相似文献   

20.
Summary Soft-X-ray generation in aluminium plasmas produced by Nd nano-second laser pulses is investigated analysing time-resolved spectra ofK-shell line emission. Time histories of line emission and electron temperature as well as the time-integrated X-ray yield were studied as a function of laser pulse duration and target position along the laser beam propagation axis. The experimental results suggest that X-ray emission is influenced by self-focusing of laser light in the plasma. Presently at Laboratoire pour l'Utilisations des Lasers Intenses, Ecole Polytechnique, 91128 Palaiseau Cedex, France.  相似文献   

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