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991.
Vinay Kumar Hemant Dave 《International Journal of Infrared and Millimeter Waves》2004,25(12):1773-1779
A submillimeter heterodyne spectrometer using continuous wave optically pumped molecular laser as local oscillator and Schottky diode as mixer was developed at Physical Research Laboratory, Ahmedabad (India) for quantitative spectroscopy of polyatomic molecules in laboratory. The experimental details of spectrometer and its application to study of molecular line parameters are presented. In particular line strength, collision line width (self and foreign) of H2S 55,054,1 transition1(579.799 GHz) have been measured. Air molecules have been used as foreign (perturbing) molecules taking Earths atmosphere into consideration2. 相似文献
992.
Lucchesini A Gozzini S 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2004,60(14):3381-3386
Some overtone absorption lines of ammonia and ethylene have been examined by using a tunable diode laser (TDL) spectrometer in the region around 12,650 and 11,800 cm(-1), respectively. The spectrometer sources are commercially available double heterostructure InGaAlAs and AlGaAs TDLs operating in the "free-running" mode. The high resolving power ( approximately 10(7) ) of the spectrometer permitted the detection and the study of the line positions of such molecules with a precision better than 0.01 cm(-1). In order to maximize the signal to noise ratio and to extract the necessary informations either on the line width and on the line position for the detected molecular resonances, the wavelength modulation spectroscopy (WMS) along with the second harmonic detection techniques have been applied. For this purpose, the fitting procedure took into account the instrumental effects and the amplitude modulation (AM) always associated with the frequency modulation (FM) of these type of sources. This technique permitted also the measurement of the collisional-broadening and -shifting coefficients by different buffer gases at room temperature. 相似文献
993.
基于线列光探测器件的光谱仪具有多光谱通道探测的优点,以及其在物质光谱分析中担当的重要角色。分析了基于线列光探测器件光谱仪的波长准确度问题,提出利用激光诱导击穿原子光谱丰富波长校准特征波长谱线的思想。实验选用光谱波长范围为200nm~600nm的凹面光栅光谱仪、2048元焦平面的CCD器件和低压汞灯,分别对铜、铝、镁、钙、硅等5种样品进行了激光诱导击穿光谱试验;利用选取的10条激光诱导原子光谱波长数据并结合低压汞灯的10条特征谱线对光栅光谱仪重新进行波长校准,获取的试验数据有力地证明了这种思想的可行性。 相似文献
994.
995.
基于线阵电荷耦合器件(CCD)的小型光谱仪具有便于携带和快速探测的优点,故特别适于现场检测应用。介绍一种自行研制的小型光栅光谱仪,它采用Czerny-Turner式光学结构,并用线阵CCD作为探测器。该光谱仪光度特性的实验检测结果证明:实验样机的光度精密度优于±0.04Abs,光度准确度为±0.04Abs(0Abs~1Abs)。实验分析了光谱仪的杂散光、光度噪声和基线平直度等指标对仪器光度准确度的影响。最后针对小型光谱仪的特点提出改善其光度特性的措施。 相似文献
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999.
Ajay Kumar D. Misra A. H. Kelkar U. R. Kadhane K. V. Thulasiram Lokesh C. Tribedi 《Pramana》2007,68(6):983-994
We have studied fast ion-atom and electron-atom collision processes using a reconditioned high resolution X-ray spectrometer.
The X-rays, generated by the collisions, are dispersed by a curved ADP crystal (Johansson geometry) and detected by a gas
proportional counter. A self-written LabVIEW based program has been used to give precise and controlled movement to the crystal
and for data acquisition. The performance was tested by detecting the Kα diagram and satellite lines of several elements.
The Kα satellite lines of Al have been studied in collision with 3–12 keV electrons and 40 MeV C4+ ions. In ion collisions as large as four L-vacancies are created simultaneously with the K-vacancy, compared to two satellites
in case of the e-impact. In addition, we have measured the X-rays from H-, He- and Li-like Si ions which arise due to the
electron loss/capture process in highly charged 80 MeV Si7+ ions in collision with thin carbon foil. Approximate charge state distribution has been obtained using this new technique.
相似文献
1000.
A. T. Khalmanov 《Journal of Applied Spectroscopy》2000,67(1):9-13
Multistage effective excitation circuits for a sodium atom in a propane-butane-air flame are studied experimentally. Consideration
is given to the effectiveness of the excitation and ionization of an Au atom following the collision scheme
. Analytical capabilities of the atomizing rod-flame system are demonstrated taking as an example the determination of Au
traces in silver nitrate. The proposed technique of determining Au traces can also be applied to other objects. Variants of
ionization through auto-ionization and Rydberg states of Au are examined.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 67, No. 1, pp. 11–14, January–February, 2000. 相似文献