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1.
本文叙述的方法是将固体铝合金样品在车床或铣床上加工成平面,然后以选好的仪器测量条件,用铝元素做内标,按照自编分析程序在MBS火花台上氩气气氛中激发,进行火花-原子发射光谱法测定。此方法快速、简便,标准样品所得分析结果基本与标称值吻合,3次测定结果相对偏差≤20%。在重复性实验中,不同时间内测定同一样品10次,10个被测元素结果的相对标准偏差RSD≤10%。  相似文献   

2.
火花—AES法测定中低合金钢中14种少量元素   总被引:1,自引:0,他引:1  
本文所叙述的方法是将固体中低合金钢样品在车床或铣床上打平。或在磨片机上磨成理想的平面。然后用选好的最佳仪器测量条件,用铁元素做内标,按照自编的分析程序在多基体火花发射台的氩气氢气中激发,进行火花原子发射光谱法测定。此法简便,快速,所得分析结果与推荐的标准值基本一致,其相对标准偏差RSD≤10%,测试结果令人满意。  相似文献   

3.
本文所叙述的方法是将固体中低合金钢样品在车床或铣床上打平,或在磨片机上磨成理想的平面.然后用选好的最佳仪器测量条件,用铁元素做内标,按照自编的分析程序在多基体(MBS)火花发射台的氩气气氛中激发,进行火花原子发射光谱法测定。此法简便、快速,所得分析结果与推荐的标准值基本一致,其相对标准偏差RSD≤10%,测试结果令人满意。  相似文献   

4.
本文所叙述的方法是将固体工业纯铁在车床或铣床上打平,然后以选好的仪器测量条件,用铁元素作内标,按照自编分析程序在MBS火花发射台的氩气气氛中激发,进行火花原子发射光谱法测定,此法快速、简便,所得分析结果基本与标准值相同,其相对标准偏差RSD≤10%,结果令人满意。  相似文献   

5.
本文采用运动电极,火花激发,讨论了膜样品分析中标样和分析样品的一致性,介绍了选用多个样品叠加摄谱对ITO膜中Sn/In浓度比的测量。结果表明分析方法的精密度和准确度满足分析要求。  相似文献   

6.
伪火花放电开关的陶瓷表面放电触发研究   总被引:6,自引:4,他引:2       下载免费PDF全文
 设计了伪火花开关的陶瓷材料表面放电触发器,该触发器体积小,结构简单,可焙烧。经大量实验表明,较传统的表面放电触发器可靠性提高,寿命延长,用它触发的伪火花开关(放电电压30~2kV)具有稳定的放电时延(50~340ns)和时延抖动(15~40ns)。由于触发电流大,因此可在极低的开关电压下触发开关,对耐受电压30kV的伪火花开关,其最低可触发开关电压可至600V。  相似文献   

7.
火花熔蚀-电感耦合等离子体光谱法(SA-ICP)用于测量锆石中铪-锆比值和锰铁矿瘤中的铈、钴、铁、铅、镍和磷。用信背比和信噪比的序贯单纯形优化法建立了用于高压火花和氩气ICP系统的六个操作参数。将磨细的样品与铜压成饼,并从样品中熔蚀出的分析物和基体元素的原子发射信号的时间相关性给出一种用火花来作选择取样的方法。测量锆石中的铪、锆浓度比的精密度为4%(相对标准偏差)。对于锰铁矿瘤,根据分析线对锰(Ⅱ)257.610纳米线强度比的光谱测定结果达到分析精密度范围为7-14%(相标准偏差)。分析的准确度用参比物USGS诺得(Nod)P-1的标准物加入法来决定,而与锰浓度的测量无关。  相似文献   

8.
激光蒸发进样ICP—AES测定地质样品中的钡和锶   总被引:3,自引:1,他引:2  
本文讨论了用连续CO2激光器蒸发地质粉末样品,ICP-AES测定Ba和Sr。在样品中加入适量的粘合剂和石墨粉关压饼,用激光全部激发。在蒸发室出口处加入了一只多我孔过滤器,一定程度上改善了系统长时间工作的稳定性。对影响激光采样和ICP-AES分析性能的参数进行了研究。实验结果表明,连续激光蒸发地质粉末样品、ICP-AES测定Ba,Sr,大部分分析结果满意。在选择的系统条件下,Ba,Sr的检出限分别为  相似文献   

9.
采用固体径迹火花自动计数器测量弱中子场下狭小空间内的中子。固体径迹火花自动计数器用贫化铀和浓缩铀电镀片作为转换靶,采用电镀法制备浓缩铀镀片和贫化铀镀片。  相似文献   

10.
激光诱导氧气火花演化的数值计算   总被引:1,自引:0,他引:1  
针对激光诱导氧气火花的演化过程,建立了二维轴对称、非定常、多组分计算模型,在流体力学基本方程组的基础上考虑化学反应动力学,并用Fluent软件进行求解,得到了氧气火花在不同时刻的压力和温度分布,分析了氧气火花演化过程中流动传热过程的一些特点,并拟合得到了冲击波半径随时间的变化关系。通过计算结果与文献结果对比,进一步阐明了激光诱导氧气火花演化过程的动理学机理,为激光诱导气体火花点火的应用奠定了基础。  相似文献   

11.
Two-dimensional scanning of a 0.6328 mum guided-light beam has been realized using noncolinear acousto-optic (AO) coplanar Bragg diffraction together with colinear AO guided-mode to substrate radiation-mode conversion in a Z-cut Xpropagation LiNbO3 proton-exchanged (PE) waveguide. The two surface acoustic (SAW) waves utilized are at the center frequencies of 500 and 200 MHz, propagating in the Y and X axes, respectively. Two-dimensional scanning of approximately 720 resolvable light beam spots, namely, 18 40 (horizontal vertical) scanning, has been demonstrated using a light beam of 1.0 mm aperture. The total number of resolvable beam spots can be greatly increased from 720 by simply utilizing SAW transducers of larger bandwidth and a light beam of greater aperture. It should also be possible to significantly increase the diffraction efficiency from 3 % by optimizing the parameters of the PE waveguide and the SAWs.  相似文献   

12.
A review of schemes for multiple access in fiber optic networks shows that a hybrid of wavelength and code division multiple access (WCDMA) combines the best features of both. In particular, the hybrid scheme retains the large information carrying capacity of wavelength division multiple access (WDMA) and flexibility of code division multiple access (CDMA). In this paper WDMA, optical CDMA (OCDMA), and WCDMA networks are discussed. In OCDMA networks, concept of incoherent and coherent coding including inverse decoding and matched filter is introduced. The delay performance of both WDMA and WCDMA networks, under the simple suboptimum access protocols based on cyclic search, is computed. It has been shown quantitatively that tuning delay significantly affects the delay performance of both WDMA and WCDMA networks. Futhermore, delay performance of WCDMA networks is always better than the WDMA networks for the same tuning delay, load, and number of users.  相似文献   

13.
Results of a study of the effect of γ-radiation on the spectral luminescence properties of cadmium tungstate crystals doped with silver, bismuth, and molybdenum cations are presented. Spectral characteristics of the nondnnnoped crystals are briefly described. Absorption and photo and X-ray luminescence spectra of the crystals taken before and after exposure to γ-radiation (5.5·104 Gy) are compared. It is found that the spectral characteristics of the crystals doped with silver, bismuth, and molybdenum cations do not change markedly after the exposure. The relation between the type of impurity-induced defects, individual characteristics of the impurity cations, and the character of the effect of γ-radiation on the spectral luminescence properties of impure crystals is analyzed (preliminarily). Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 55–60, January–February, 1997.  相似文献   

14.
A simple technique of pulse compression, based on the linear chirp compensation of self-phase modulation (SPM) spectra in dispersion shifted fibers, is demonstrated. The optimization procedure is carried out, for a short span of a single-mode fiber, using a parabolic law, which describes the behavior of the squared output pulse width versus the pump peak power in the case of Gaussian pulses. The experimental results give a minimum pulse duration of 233 fs, which is in good agreement with the model. Shorter and coherent pulses, down to 90 fs, have been obtained by inserting an interference filter at the optical output.  相似文献   

15.
The Shanghai Synchrotron Radiation Facility(SSRF)booster ring,a full energy injector for the storage ring,is deigned to accelerate the electron beam energy from 150MeV to 3.5GeV that demands high extraction efficiency at the extraction energy with low beam loss rate when electrons are ramping.Closed orbit distortion(COD)caused by bending magnet field uniformity errors which affects the machine performance harmfully could be effectively reduced by bending magnet location sorting.Considering the affections of random errors in measurement,both ideal sorting and realistic sorting are studied based on measured bending magnet field uniformity errors and one reasonable combination of bending magnets which can reduce the horizontal COD by a factor of 5is given as the final installation sequence of the booster bending magnets in this paper.  相似文献   

16.
17.
We measure the waveform and phase curves of short optical pulses before and after transmission over different lengths of fibers by use of the pulse analyzer with the frequency-resolved optical gating (FROG),and numerically simulate pulse evolution under the experimental conditions.The nonlinear coefficient of the fiber is given by comparing the experimental results with the numerical ones.Difference between the experiment and numerical simulation is analyzed.  相似文献   

18.
Resonance scattering of elastic spherical shell and cylindrical shell while the surrounding fluid medium has absorption is studied. The normal mode solution derived using exact elastic theory and the separation of variables is still applicable. However, the scattering form function has to be modified for the absorbing medium, otherwise the unreasonable result would be obtained. The backscattering form function in the absorbing medium is redefined, and the form function of elastic spherical and cylindrical shell with vacuum or solid matter filled is calculated in various absorption conditions. The results show that the absorption of surrounding fluid leads to notable attenuation of the coincidence resonances in the mid-frequency, but it has a little influence on the low-frequency resonance scattering induced by the filler inside the shell.  相似文献   

19.
A versatile and low-cost single-beam self-referenced phase-sensitive surface plasmon resonance(SPR)sensing system with ultra-high resolution performance is presented.The system exhibits a root-mean-square phase fluctuation of ±0.0028.over a period of 45 min.i.e.a resolution of±5.2×10-9 refractive index units.The enhanced performance has been achieved through the incorporation of three design elements:a true single-beam configuration enabling complete self-referencing so that only the phase change associated with SPR gets detected,a differential measurement scheme to eliminate spurious signals not related to the sensor response,and the elimination of retardation drifts by incorporating temperature stabilization in the liquid crystal phase modulato .Our design should bring the detection sensitivity of non-labeling SPR biosensing closer to that achievable by conventional fluorescence-based techniques.  相似文献   

20.
Ta2O5 films are prepared on BK7 substrates with conventional electron beam evaporation deposition.The effects of SiO2 protective layers and annealing on the laser-induced damage threshold (LIDT) of the films are investigated.The results show that SiO2 protective layers exert little influence on the electric field intensity(EFI)distribution,microstructure and microdefect density but increase the absorption slightly.Annealing iS effective on decreasing the microdefect density and the absorption of the films.Both SiO2 protective layers and annealing are beneficial to the damage resistance of the films and the latter is more effective to improve the LIDT.Moreover,the maximal LIDT of Ta2O5 films is achieved by the combination of SiO2 protective layers and annealing.  相似文献   

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