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41.
《Analytical letters》2012,45(14):1189-1194
Abstract The paper describes a technique for quantitative determination of silicon in organic monomer and polymer materials based on low-temperature decomposition of samples in rf-discharge oxygen plasmas. The final step of analysis involves gravimetric determination of silicon in the form of silicon dioxide. The presence of fluorine (up to 50%) does not interfere with the determination of silicon. 相似文献
42.
《Analytical letters》2012,45(11):1005-1012
Abstract A procedure for the determination of propoxyphene (α-d-dimethylamino-1, 2 -diphenyl-3 -methyl-2 -propionoxybutane) in plasma is reported. The method is based on the electron capture characteristics of propoxyphene. The plasma is rendered basic to generate the free amine and extracted with ether. The extract is analyzed by gas chromatography using a 4 foot OV-225 column. An internal standard of imipramine hydrochloride is used to quantitate the propoxyphene. This internal standard is carried through the entire procedure. The ratio of the peak heights of propoxyphene to imipramine is compared to ratios obtained from standards placed in plasma and treated in the same manner as the samples. Six subjects were given propoxyphene at different time intervals, and the data are presented concerning these subjects. 相似文献
43.
刘红秀 《核聚变与等离子体物理》1986,(1)
一、引言 文[1]建立了关于等离子体色散函数的四极点近似式Z_(53),但其相对误差较大。本文研究结果表明,根据等离子体色散函数的幂级数展开与渐近展开的直接形式,适当地截取有限项,即可解决大多数关于等离子体色散函数Z(s)的数值计算问题。 相似文献
44.
使用光发射谱(OES)对甚高频等离子增强化学气相沉积(VHF-PECVD)技术沉积硅薄膜时的等离子体发光基团的空间分布进行了在线监测和研究. 研究表明:等离子体的不同发光基团都存在着一个中间强度较大的区域和两边电极附近的暗区;增大硅烷浓度和提高辉光功率都会增大SiH*峰强度;硼烷的加入,使得SiH*和Hα*峰强度增大,但硼烷流量变化的影响很小;硼烷流量增大,材料的晶化率下降,而I[Hα*]关键词:
甚高频等离子增强化学气相沉积
等离子体
发光基团
空间分布 相似文献
45.
绕弹体的超声速气流与发动机喷流相互作用,在尾部形成复杂的干扰流场。本文用有限差分法求解全N-S方程,对这一复杂流场进行了数值模拟,得到了实验观察到的各种流场结构及其随喷口压力比的变化规律。外流M∞=1.94,Re∞=2.2×105,喷流Mj=3.0,喷口压力比pj/p∞分别为1.03,0.527,0.15三种。差分算法为一种改进的Beam-Warming格式。计算底部压力和激波在喷流中心的反射位置与实验数据进行了比较,吻合较好。 相似文献
46.
激光等离子体能量角分布及吸收定标律 总被引:1,自引:0,他引:1
主要研究激光平面靶等离子体发射能量角分布及吸收定标律。实验利用高斯型1.06μm激光脉冲,其能量为2~50J,脉冲宽度为0.3~2.2ns,靶面平均辐照强度为1.8×1013~1.1x10~(15)W/cm~2,光束以25°角入射。实验采用了Au、Ag、Ti、Al和C_8H_8等厚靶。用等离子体卡计测量靶面吸收的激光能量。用指数函数拟合实验数据,给出了吸收效率分别作为激光强度、脉冲宽度和靶材料原子序数的函数的定标关系式。这些关系式定性地与逆轫致吸收的理论关系式相一致。 相似文献
47.
本文描述了用膜吸收法测量激光等离子体辐射温度空间分布的原理和方法给出了柱形缝靶轴向辐射温度随空间位置变化的特征,对测量结果进行了分析讨论。 相似文献
48.
Diagnosis of phasma in CCD damage process induced by laser 总被引:1,自引:0,他引:1
In this paper, the shapes of plasma produced by a Q-switched YAG laser acted repeatedly upon a CCD with MOS structure are used, to investigate the destroying process of the optoelectronic device. The experimental results of CCD destroyed by a 1.06μm laser beam with a pulse width of 15 ns are given. 相似文献
49.
The effects of the ambient air pressure level on the performance of plasma synthetic jet actuator have been investigated through electrical and optical diagnostics.Pressures from 1 atm down to 0.1 atm were tested with a 10 Hz excitation.The discharge measurement demonstrates that there is a voltage range to make the actuator work reliably.Higher pressure level needs a higher breakdown voltage,and a higher discharge current and energy deposition are produced.But when the actuator works with the maximum breakdown voltage,the fraction of the initial capacitor energy delivered to the arc is almost invariable.This preliminary study also confirms the effectiveness of the plasma synthetic jet at low pressure.Indeed,the maximum velocities of the precursor shock and the plasma jet induced by the actuator with maximum breakdown voltage are independent of the ambient pressure level;reach about 530 and 460 m/s respectively.The mass flux of the plasma jet increases with ambient pressure increasing,but the strength of the precursor shock presents a local maximum at 0.6 atm. 相似文献
50.
Energy spectrum of multi-radiation of X-rays in a low energy Mather-type plasma focus device 下载免费PDF全文
The multi-radiation of X-rays was investigated with special attention to their energy spectrum in a Mather-type plasma focus device (operated with argon gas). The analysis is based on the effect of anomalous resistances. To study the energy spectrum, a four-channel diode X-ray spectrometer was used along with a special set of filters. The filters were suitable for detection of medium range X-rays as well as hard X-rays with energy exceeding 30 keV. The results indicate that the anomalous resistivity effect during the post pinch phase may cause multi-radiation of X-rays with a total duration of 300 ± 50 ns. The significant contribution of Cu-Kα was due to the medium range X-rays, nonetheless, hard X-rays with energies greater than 15 keV also participate in the process. The total emitted X-ray energy in the forms of Cu-K and Cu-K/3 was around 0.14 ± 0.02 (J/Sr) and 0.04 ±0.01 (J/Sr), respectively. The total energy of the emitted hard X-ray (〉 15 keV) was around 0.12± 0.02 (J/Sr). 相似文献