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191.
原子发射双谱线法测火焰温度的实验研究 总被引:1,自引:0,他引:1
通过光谱仪测量火焰中K(766.5,769.9 nm)原子发射谱线的相对强度比来获得火焰温度。介绍了测量原理、测量方法、实验系统。在黑体炉炉膛达到热力学平衡状态下,进行原子发射双谱线法和热电偶测温的对比实验,结果两种方法所测温度相关性较好,实验证明了该方法的可行性。用该方法测量煤粉和木材的火焰温度,结果和实际相符合。 相似文献
192.
Stephanie Hansen G.S.J. Armstrong S. Bastiani-Ceccotti C. Bowen H.-K. Chung J.P. Colgan F. de Dortan C.J. Fontes F. Gilleron J.-R. Marquès R. Piron O. Peyrusse M. Poirier Yu. Ralchenko A. Sasaki E. Stambulchik F. Thais 《High Energy Density Physics》2013,9(3):523-527
Collisional-radiative atomic models are widely used to help diagnose experimental plasma conditions through fitting and interpreting measured spectra. Here we present the results of a code comparison in which a variety of models determined plasma temperatures and densities by finding the best fit to an experimental L-shell Kr spectrum from a well characterized, but not benchmarked, laser plasma. While variations in diagnostic strategies and qualities of fit were significant, the results generally confirmed the typically quoted uncertainties for such diagnostics of ±20% in electron temperature and factors of about two in density. The comparison also highlighted some model features important for spectroscopic diagnostics: fine structure was required to match line positions and relative intensities within each charge state and for density diagnostics based on emission from metastable states; an extensive configuration set was required to fit the wings of satellite features and to reliably diagnose the temperature through the inferred charge state distribution; and the inclusion of self-consistent opacity effects was an important factor in the quality of the fit. 相似文献
193.
The boundary of the zone in which sputtered atoms are thermalized in the substrate–target drift space during the ion-plasma magnetron deposition of films is determined theoretically and experimentally. A comparison of the thicknesses of films deposited on the front and back sides of substrates situated at different distances from the target makes it possible to divide the flow of atoms sputtered toward substrates into direct and diffusion flows and to determine the dimensions of the spatial zone in which sputtered atoms are thermalized. The experimental data are in quantitative agreement with the results of a statistical simulation of the thermalization process of atomic particles during the ion-plasma deposition. This simulation enables optimization of the technology of defect-free growth of films with uniform thickness on substrates with complex 3D configuration. 相似文献
194.
《International journal of environmental analytical chemistry》2013,93(3):123-132
Heating a suspension of Bisphenol A diglycidyl ether (BADGE) in 20 : 80 tetrahydrofuran/water at 70°C and subsequent passage of the resulting solution through C18 columns allowed isolation and purification to > 97% of each of the two hydrolysis products 2-[4-(2,3-dihydroxypropoxy) phenyl]-2-[4-(2,3-epoxypropoxy)phenyl]propane (1HP) and 2,2-bis[4-(2,3-dihydroxypropoxy)phenyl] propane (2HP), which were characterized by UV, IR, 1H and I3C NMR spectroscopy and mass spectrometry. 相似文献
195.
A fast procedure has been developed for the direct determination of paint solvents. The method is based on the injection of small volumes of untreated solvent mixtures into a heated Pyrex glass reactor in which the sample is volatilized and introduced by means of a flow of nitrogen into an IR multiple pass gas cell and the spectrum in the mid-IR region is registered as a function of time. Data found for samples are interpolated in calibration graphs obtained by injecting different volumes of pure compounds which constitute the solvent mixture. A methylisobutylketone (MIBK) toluene mixture was used as test system to develop the proposed procedure. The method provides a limit of detection of the order of 1–4 μg, a relative standard deviation of the order of 0.4 to 2% for five independent measurements, and recovery percentage values from 99.8 till 103.6 %. A commercial sample of polyurethane paint solvent has been analysed by the developed procedure. 相似文献
196.
《Analytical letters》2012,45(9):671-687
Abstract Methods were investigated to measure exhaust emission rates of individual low-molecular-weight phenols from gasoline and diesel vehicles driven on a chassis dynamometer using the FTP driving cycle. An extraction procedure to isolate the phenols from exhaust scrubs was evaluated. Separation of individual phenols was done by gas chromatography, with detection by a flame ionization detector. Phenol identifications were confirmed by mass spectroscopy. Results of a limited survey of gasoline and diesel vehicles are reported. 相似文献
197.
《Journal of Coordination Chemistry》2012,65(8):1371-1380
Synthesis and characterization of zinc and cobalt phthalocyanines substituted with biphenylmethylpropionic acids, methyl-o-tolylpropionic acids, and methyl-p-tolylpropionic acids are described in this study. The new compounds have been characterized by elemental analyses, FT-IR, UV-Vis, MALDI-TOF, and 1H NMR spectroscopy. All new compounds are soluble in THF, DMF, DMSO, and dilute sodium hydroxide solution. The influence of the carboxylic acid and bulky biphenyl, ortho-methylbenzyl and para-methylbenzyl groups on the spectroscopic properties has been investigated. UV-Vis experiments suggest that the tendency of phthalocyanines to aggregate in polar solvents is significantly reduced owing to the carboxylic acid groups and bulky peripheral substituents. 相似文献
198.
J. Swiatkiewicz 《Phase Transitions》2013,86(9-10):891-896
Transient behaviour of the excited states originated from the neutral and the charged species is discussed using data from time-resolved experiments. Complex transient characteristics obtained for the slightly charged poly-(bithiophene) film during electrochemical doping were explained in terms of sequential molar fraction changes of the neutral species, the radical cation and the π-dimerized radical cations. Femtosecond transient absorption measurement carried out in time range of 0-4 ns for a two-photon excited dye reveals a multi-exponent decay with well separated relaxation times and the distinct relaxation mechanisms. At high irradiance and a sufficient fluence, the multi-photon excitation processes affect the subpicosecond response and lead to formation of the photo-products. 相似文献
199.
A Maleic anhydride–Octene-1–Vinylbutyl Ether terpolymer was synthesized via the radical terpolymerization method in order to prepare a new matrix for CdS nanocrystal synthesis. CdS nanocrystals were synthesized through the reaction of thiourea with cadmium chloride. The synthesized terpolymer/CdS nanocrystal composites were characterized by several methods. Energy Dispersive X-ray analysis, Raman spectroscopy and powder X-ray diffraction methods. The room temperature UV–visible absorption spectra show a shift of the absorption edge towards higher energies. The band gap of the CdS nanocomposite is bigger than that of bulk CdS. Raman spectrum exhibits characteristic peaks of CdS. Images of the nanocomposite obtained with Atomic Force Microscopy and Transmission Electron Microscopy are the evidences of CdS nanocrystal formation in the terpolymer. Thermal investigation shows that the nanocomposite is more thermostable than the terpolymer which could be useful for application in thermo aggressive medium. 相似文献
200.
研究了冷冻-解冻处理对A1CI3溶液团簇结构和AICl3与血清白蛋白相互作用的影响。测定了AICl3溶液冷冻-解冻处理前后电导率的变化,发现AICI3溶液经冷冻处理后,电导率有明显增加。采用紫外分光光度法和荧光光谱法对冷冻前后AICI3溶液与血清白蛋白相互作用的研究表明,A1C13溶液经冷冻-解冻处理后,与血清白蛋白的相互作用变弱,配位诱导作用降低,静态猝灭作用变小,这种相互作用变弱的效应是由于水的分子团簇结构变化引起的。 相似文献