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1.
空心玻璃微球D2/Ne混合气体充气工艺   总被引:2,自引:2,他引:2  
本工作主要研究空心玻璃微球对D2和Ne气体渗透系数的差异,以及研究采用热扩散法在高压充气系统上向空心玻璃微球充入D2/Ne混合气体的充气工艺。利用干涉条纹法测量了在充气和保气时Ne的气体渗透系数,它们分别为KNe,350℃=2.6×10-18和KNe,25℃=8.0×10-22mol•m-1•s-1•Pa-1。根据D2的气体渗透系数确定了玻璃微球充D2/Ne混合气体的充气方法和充气平衡时间,平衡时间以充纯Ne时间为准。此外,还研究了空心玻璃微球充入混合气体后的保气性能。  相似文献   

2.
不同参数对GDP薄膜的结构与力学性能的影响   总被引:2,自引:2,他引:0  
采用辉光放电等离子体聚合技术,在不同制备参数条件下,制备了辉光放电聚合物(GDP)薄膜。利用傅里叶变换红外吸收光谱对GDP薄膜的化学结构组成进行了分析,采用纳米压痕技术对GDP薄膜的硬度及杨氏模量进行了表征,探讨了GDP薄膜的化学结构组成、硬度及杨氏模量随制备参数的变化规律。研究表明:随着工作气压和反式二丁烯与氢气(T2B/H2)流量比逐渐降低,GDP薄膜中SP3(CH3)基团随之降低,SP2(CH2)基团含量和SP3(CH1,2)随之增加;GDP薄膜的硬度与杨氏模量随着工作气压、T2B/H2流量比的降低而逐渐增大。  相似文献   

3.
采用低压等离子体聚合装置,在溴化钾单晶盐片上制备了气压、功率、反式二丁烯(T2B)与氢气流量比3个沉积参数系列的辉光放电聚合物(GDP)涂层。对3个系列涂层各自的红外光谱进行比较分析,结合高斯拟合,定量地讨论涂层内部SP3(CHx)与SP2(CHx)键的相对含量的变化规律,且探讨了各系列沉积参数对气体分子在等离子体发生区的离解效率和沉积过程活性粒子与涂层新生表面及亚表面相互作用的影响。结果表明,在低气压、较高功率和低流量比参数下,GDP涂层内SP3(CH3)和氢元素的含量相对较低,SP2(CH2)和碳元素的含量相对较高。  相似文献   

4.
在室温、真空条件下,利用加速器产生的高能电子束辐照聚二甲基硅烷(PDMS)试样,研究吸收剂量对其结构的影响。通过气相色谱质谱联用分析可知,辐照过程中产生了少量H2和CH4,且H2的产率高于CH4。FT-IR、激光拉曼光谱以及XRD分析结果表明,经超高剂量(MGy级)辐照后,聚二甲基硅烷的化学结构未发生明显变化,其晶态结构也未遭破坏。这些结果说明,PDMS具有异乎寻常的耐辐射性能,这可能归因于其主链上规整Si—Si键的σ电子离域运动所形成的σ共轭体系的特殊结构。  相似文献   

5.
高纯氘中杂质的低温气相色谱分析   总被引:1,自引:2,他引:1  
实验研究采用5A分子筛和氧化铝充填色谱柱分别在常温和低温(77K)下对D2中的O2、N2以及H2、HD等杂质进行定量分析测量,以建立1种准确实用的分析方法。研究结果表明,该方法对H2、HD的最低检测浓度可达(150~200)×10-6,能够满足高纯氘制备过程中对杂质的定量分析要求。  相似文献   

6.
氘气中氢同位素的低温气相色谱法测定   总被引:2,自引:0,他引:2  
针对高纯氘气中H2、HD与D2等氢同位素气体间不易分离分析的特点,以5A分子筛微填充石英毛细管色谱柱,在-95℃下对氢同位素进行分离,以气相色谱-脉冲放电氦离子化检测器对氢同位素进行分析。研究建立的H2、HD与D2等同位素气体测定方法精密度小于15%,最小检出摩尔分数为1×10-6。  相似文献   

7.
以Pt-Ti(镀铂钛)为阳极,Ti为阴极,对HNO3介质中的H2C2O4进行恒电流电解,考察HNO3介质中H2C2O4电解动力学特性及其影响因素,并初步探讨HNO3介质中H2C2O4的电解氧化机理。研究结果表明:电流密度控制在25~37mA/cm2、HNO3浓度为2~3mol/L、温度为30~40℃时,电解效果最佳;微量金属离子(Fe3+、MnO-4、Ag+)的存在对H2C2O4的电解起催化作用,能较大提高电解速率;电解氧化法破坏H2C2O4的效率高于KMnO4蒸煮法,在工业中有潜在的应用前景。  相似文献   

8.
氧化硼对铁磷酸盐玻璃陶瓷固化体的影响   总被引:1,自引:0,他引:1  
研究了不同B2O3掺量对铁磷酸盐玻璃陶瓷高放废物固化体结构和性能的影响。应用溶出速率法(DR)对固化体进行了化学稳定性测试,使用傅里叶变换红外光谱(FTIR)和X射线衍射(XRD)方法研究了样品的结构。研究结果表明:玻璃陶瓷固化体的主晶相为独居石;B2O3的引入对玻璃陶瓷固化体的化学稳定性影响较大,以10%(摩尔分数)的B2O3代替Fe2O3制得的固化体化学稳定性最佳,其28d的质量浸出率约为7.81×10-9g•cm-2•min-1;试样中存在大量正磷酸基团[PO43-和少量焦磷酸基团[P2O74-,无偏磷酸基团[PO3-存在,固化体中的B主要以[BO4]四面体基团形式存在。  相似文献   

9.
提出了一种快速、准确测量电子在气体中漂移速率的新方法。通过分析电子在双栅电离室中两个栅极上产生的感应信号波形来确定电子漂移的起止时刻,从而得出电子在一定约化场强下的漂移速率。采用数据采集卡(waveformdigitizer)对电离室的极板信号进行记录。测量了电子在8种混合比例的Ar+CH4气体中漂移速率随约化场强的变化曲线。通过分析实验数据,得到任意混合比例的Ar+CH4气体中电子漂移速率的计算公式。  相似文献   

10.
为了解在惰气环境Pu(OH)4(am)与碳酸盐溶液中HCO-3,CO2-3的配位行为,考察了放置时间对Pu总浓度的影响;同时也考察了pH值、碳酸根总浓度变化对碳酸盐溶液中Pu的主要存在形态及溶解总浓度的影响。实验结果表明,HCO-3离子与Pu(OH)4(am)生成[Pu(OH)4(HCO3)2]2-(lg K=-2.61±0.18, lgβ=54.25±0.18)或[Pu(OH)2(CO3)2]2-(lgK=-2.61±0.18, lgβ=46.91±0.18);CO2-3离子与Pu(OH)4(am)生成[Pu(OH)4(CO3)2]4-(lgK=-3.52±0.11, lgβ=53.33±0.11)。可能的配位反应方程式为: Pu(OH)4(am)+2HCO-3 = [Pu(OH)4(HCO3)2]2-, Pu(OH)4(am)+2HCO-3 =[Pu(OH)2(CO3)2]2-+2H2O, Pu(OH)4(am)+2CO2-3=[Pu(OH)4(CO3)2]4-。  相似文献   

11.
Experiments on lower hybrid wave(LHW)coupling were investigated in the HT-7 tokamak.Good coupling of LHW plasma has been demonstrated at different conditions in the HT-7 tokamak.Relevant results have proved that LHW-plasma coupling is affected by the phase difference between adjacent waveguides.Furthermore,the edge density around the grill and relevant coupling can be adjusted by changing the plasma line average density or the gap value between the LH grill and the last closed flux surfaces(LCFS).It is found that the coupling of LHWs becomes poor when the edge density around the LH grill is large enough in the HT-7tokamak,and that coupling remains good with a proper edge density.With increasing LHW power,it is also found that the reflection coefficients(RCs)increase due to non-linear effects under conditions of low edge recycling,but can decrease under high edge recycling.The edge density depends mainly on the competition between the ponderomotive force(PMF)and the edge recycling intensity in the HT-7 tokamak.  相似文献   

12.
Lower hybrid wave (LHW)-plasma coupling and lower hybrid current drive (LHCD) experiments in divertor, including single-null and double-null, and limiter configurations were conducted systematically in EAST. A maximum power for launched LHW is 1.4 MW and the plasma current with LHCD is about 1 MA. It is indicated that the coupling is best in limiter configuration, then in single-null one, while worst in double-null one. Study in current drive efficiency by a least squares fit shows that there is no obvious difference in drive efficiency between the double-null and the single-null cases, whereas the efficiency is a slightly lower in the limiter case. The effect of plasma density on the current drive efficiency is due to the influence of density on impurity concentration.  相似文献   

13.
Study on the characters of energy confinement in both ohmic and Lower Hybrid Wave (LHW) discharges on EAST is conducted and the linear ohmic confinement (LOC), saturated ohmic confinement (SOC) and improved ohmic confinement (IOC) regimes are investigated in this paper. It is observed that an improved confinement mode characterized by both a drop of Dα line intensity and an increase in line average density can be triggered by a gas puffing pulse.  相似文献   

14.
Neutron emission in EAST was investigated by a time-resolved monitor systems which consist of four 3He proportion counters and a 235U fission chamber. The D-D neutron flux increased approximately an order of magnitude during the 27 MHz Ion-cyclotron resonance frequency (ICRF) heating, demonstrating that the ICRF wave heated the plasma effectively. In addition in LHW experiment with higher plasma parameters D-D neutrons were also detected. However, a mass of photoneutrons were generated in ohmic discharges with low plasma density. Effect of plasma density on the production of photoneutrons was studied, and it is found that LHW can suppress the runaway electrons and reduce the photoneutrons effectively.  相似文献   

15.
为在EAST装置中优化电子回旋波与低杂波双波协同的电流驱动效率,从而获得更大的协同驱动电流以维持长脉冲运行,本文以双波协同驱动电流的物理机制为基础,运用模拟程序C3PO/LUKE对EAST参数下电子回旋电流驱动与低杂波电流驱动的协同效果进行了数值模拟计算,给出了协同电流和协同因子。计算结果表明:当两波驱动电流密度峰值的位置一致时协同效果最佳;而电子密度和电子温度的增加可能导致两波重叠区域的变化进而影响协同效果。  相似文献   

16.
The electron density within the volume of the tungsten divertor of the Experimental Advanced Superconducting Tokamak (EAST) is calculated based on Dε line (396.9 nm) Stark broadening (SB) measurements. The quasistatic approximation is employed in the SB calculation of the Dε line. The influences of other broadening mechanisms on the calculation error of electron density have been evaluated. The SB method is applied to the study of spatial distribution and time evolution of the electron density in the W divertor. Two electron density bands are observed in the detached divertor plasma during an L-mode discharge sustained by low hybrid wave (LHW) heating, which could be related to the striated particle flux distribution induced by LHW. After the onset of detachment, the upper electron density band corresponding to outer strike point firstly increases then decreases, while the lower density band corresponding to striated particle flux increases continually although the electron densities from Langmuir Probes at the divertor plate keep a descending trend. This could indicate a downward movement of the radiation region that approximately moves along the magnetic field lines after the onset of detachment.  相似文献   

17.
作为惯性约束核聚变(ICF)第一代靶丸,空心玻璃微球(HGM)内充燃料气体的组分、比例和密度均有严格要求,气体总量的测定至关重要。介绍了同位素稀释质谱法(IDMS)测定空心玻璃微球内氘气气体总量的分析方法。该方法采用氢气为稀释剂,活性炭作为吸附剂制备氘气和氢气的混合气体,用质谱计测定样品中氢同位素丰度。通过热力学公式推导、计算,求得HGM内氘气摩尔数。实验结果表明:用IDMS法测量HGM内痕量氘气总量切实可行,其测量下限为10-8 mol,测量结果的相对标准偏差小于5%(n=4或3,按照极差法计算),符合测量要求。  相似文献   

18.
Propagation of intense femtosecond laser pulses (60 fs, 800 nm, 120 mJ, 6×1017 W cm-2 in vacuum) in supersonic (CD4)N and (D2)N cluster jets at different background pressures was studied. Pump-probe interferometry is employed to investigate the propagation of laser beams in dense cluster jets by examining the electron density distribution of plasma channels. It was found that propagation effects, including ionization-induced defocusing and laser attenuation of incident pulses, are very different in the (CD4)N and (D2)N cluster jets. Different ionization states of CD4 and D2 molecules were observed by analyzing the transverse electron density profiles of the plasma channels and should be considered as a major reason for the differences in the propagation effects. Numerical simulations of the nonlinear propagation of femtosecond laser pulses in (CD4)N and (D2)N cluster jets were performed, and the results indicated a good reproduction of the experimental data.  相似文献   

19.
An upgraded infrared (IR) imaging system which provides a wide field of view (FOV) has been installed on the Experimental Advanced Superconducting Tokamak (EAST) to monitor the surface temperatures on plasma facing components. Modified magnetic topology induced by lower hybrid wave (LHW) can lead to the formation of striated heat flux (SHF} on divertor plates which can be clearly observed by IR camera. In this paper, LHW power modulation is applied to analyze the appearance of SHF. It is also demonstrated that deuterium (D) pellet injection and supersonic molecular beam injection (SMBI) can to some extent reduce the heat flux on the outer strike point (OSP), but enhance the SHF on lower outer plates (LOP) of divertor. This may provide an optional approach to actively control the distribution of heat flux on diveror plates, which can protect materials from long duration high-heat flux.  相似文献   

20.
It is known that gas flow rate is a key factor in controlling industrial plasma processing. In this paper, a 2D PIC/MCC model is developed for an rf hollow cathode discharge with an axial nitrogen gas flow. The effects of the gas flow rate on the plasma parameters are calculated and the results show that: with an increasing flow rate, the total ion(N+2, N+) density decreases, the mean sheath thickness becomes wider, the radial electric field in the sheath and the axial electric field show an increase, and the energies of both kinds of nitrogen ions increase;and, as the axial ion current density that is moving toward the ground electrode increases, the ion current density near the ground electrode increases. The simulation results will provide a useful reference for plasma jet technology involving rf hollow cathode discharges in N2.  相似文献   

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