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71.
Real-time optical emission spectroscopy (OES) was used to monitor the deposition of TiN both from mixtures of tetrakis(dimethylamino)titanium (TDMATi)-N2 and TiCl4-H2-N2 in an electron cyclotron resonance chemical vapor deposition system. The accurate control of the ratio of the emission intensities of ionized nitrogen at 391.4 nm and molecular nitrogen at 357.7 nm (N 2 + /N2) led to low temperature deposition of stoichiometric TiN (Ti/N ≈ 1) and very low resistivity in both cases. It was found that high ion density plasmas are crucial for a considerable reduction of the deposition temperature while maintaining good film quality. OES shows that the abundance of certain excited plasma species is not only dependent on the gas mixture and the deposition parameters, such as total pressure and microwave power, but also is strongly affected by the magnetic field configuration. The deposition rate and the film resistivity can be related to the emission intensity ratio, I(N 2 + )/I(N2). Finally, the two processes are compared in terms of the quality of as-deposited and heat-treated films. The comparison shows that the films obtained with TDMATi exhibit lower resistivity and are thermally more stable than with TiCl4.  相似文献   
72.
This paper proposes a quick, novel method for tin determination in organotin chemicals by slurry nebulization inductively coupled plasma atomic emission (ICP-AES) spectrometry. The method was tested by the measurement of five organotin carboxylate complexes of known composition for obtaining simple stoichiometric data. The slurries were prepared by first dissolving the organotins in an adequate solvent (methanol, pyridine or acetone) well miscible with water and then adding this solution drop-by-drop to a 0.005% TX-100 tenzide solution while maintaining intensive mixing. Dynamic laser light scattering experiments showed that the average equivalent particle size in the resulting slurry was ≈0.3 μm for all samples and solvents. Under suitable ICP-AES measuring conditions, the signal recoveries were found to be between 101.8 and 106.6%, which allowed direct nebulization and calibration against aqueous solutions. Typically, 70 μg l−1 detection limit and 1–5% relative S.D. on five replicates can be achieved by the described method.  相似文献   
73.
An inductively coupled plasma atomic emission spectrometry (ICP-AES) procedure has been developed and examined for the determination of boron content (0.01 up to about 2% B) in boron-alloyed steels such as POLDI ATA BOR (65% Fe, 19%Cr, 12% Ni, 1.5% Mn, 1% B), POLDI ATA BOR EXTRA (62% Fe, 18% Cr, 13% Ni, 2.5% Mo, 1.5% Mn, 1% B) and POLDI ATA BOR-R (75% Fe, 18% Cr, 3.5% Ti, 1.8% B). The steel sample is dissolved with a mixture of hydrochloric, nitric, sulfuric and phosphoric acids in a quartz vessel. Borides of alloyed metals, especially of iron and chromium, are quantitatively decomposed. The presence of phosphoric acid in a sample solution reduces the volatility of boric acid with water vapour.Presented in part at the 1989 European Winter Conference on Plasma Spectrochemistry, Reutte, Austria  相似文献   
74.
Cyanophenyl as ancillary acceptor to modify donor-acceptor compound,plays an effective role in shifting the emission color to deep red and maintaining the luminescent efficiency.  相似文献   
75.
The equilibrium solubility of CsCl-CeCl3-HCl(11%)-H2O qua-ternary system at 25℃ has been determined by the physicchemical analysis method ,and the phase diagram was plotted, Two new double salts 3CsCl.CeCl3.3H2O and CsCl.CeCl3.4H2O obtained from the complicated system were identified and characterized by XRD,TG-DTA ,DSC,UV and fluorescence spectroscopy, Studies on the fluorescence excitation and emission show that 3CsCl.CeCl3.3H2O and CsCl.CeCl3.4H2O have upconversion luminescence of infrared-visible range,and the upconversion emission intensity increases with the increase of ratio of CeCl3 in CsCl.  相似文献   
76.
The composition and concentration of polycyclic aromatic compounds (PAC) in fuels. Theier combustion products and in the atmosphere remains a topic of considerable interest. Despite the wealth of literature on the identification of PAC, speciation at low concentrations remains difficult due to instrument limitation and the complexity of fuel and environmental samples. Consequently on line sample preparation procedures (SPE, SFE, LC, etc.) are becomeing an increasingly important step in the analysis procedure particularly where sample clean-up and fractionation are essential for improving analytical resolution. In this study a normal phase high pressure analytical resolution. In this study a normal phase high pressure liquid chromatography-gas chromatography (LC-GC) system has been developed to provide quantitative analysis of samples, as diverse as coal liquids, petroleum fuels, diesel exhaust particulates, and urban air particulates. Separation and identification of parent and alkylated PAH, hetercycline nitro-and oxy-PAC can be achieved by direct coupling to an atomic emission detector and a bech top mass spectrometer. For both systems the primary LC separation combined with the large sample volume transferred to GC vastly improves detection limits. Furthermore the complimentary nature of the two detectors used enables the positive indentification of many unknowns.  相似文献   
77.
本工作用 ICP-AES 法测定稀土-6063变形铝合金中 La、Ce、Pr、Nd、Sm、Gd、Fe、Mg、Ti、Zn,Cu 和 Mn,本方法不用化学分离,可一次同时测定这些元素,并做了 ICP光源参数、基体量变化、酸度(HCl)变化、稀土总量变化、共存元素 Fe 和 Mg 量的变化对被测元素的影响。本方法速度快、准确度高(除 Cu 稍差)。回收率91.0~110.0%,相对标准偏差±1.4~8.0%。  相似文献   
78.
研究了用5mol/L盐酸煮沸提取烟叶中的部分金属元素,用ICP-AES测定浸提液,K、Ca、Mg、Cu、B、Ba、Zn获得了较满意的结果,P、Fe、Mn的测定结果稍微偏低。此方法操作简便、快速安全,特别适合大批量烟草样的快速检测。与硝酸-高氯酸湿消化法进行对照,结果吻合得较好。并测定了国家烟草标准样品GBW08514和GBW08515,其结果与标准值相符。  相似文献   
79.
An isotope dilution method for the determination of chloride ion in aqueous samples is described. The method makes use of the isotopic shift in the rotational lines of the 1–0 band of HCl emitted in the near infrared region of the spectrum by vibrationally excited HCl molecules present in a hydrogen/entrained air flame. Chloride ion in the sample is converted to chlorine gas by electrolysis and swept into a hydrogen/entrained air flame where it is converted into HCl. Because isotope dilution is an absolute method of analysis, matrix effects are minimized, and the chlorine generation step need not be quantitative. With the system described in this paper, samples must contain at least 9 mg of chloride ion per ml, and a 2-ml sample is required. Over the range from 10 to 30 mg Cl ml−1, the average error was −0.96%, and the average relative standard deviation was 3.3% for seven samples using seven of the more intense lines in the P branch. Compared with standard silver nitrate titrations, the isotope dilution procedure was not affected by such common interferences as bromide ion and iodide ion. The technique was applied to several seawater samples from different regions.  相似文献   
80.
光谱实验室的建设和管理   总被引:1,自引:0,他引:1  
阐述冶金、铸造等行业用于金属成分分析的直读发射光谱仪实验室的建设和管理。从仪器的调研、选型,实验室选址,基础设施设备的准备,仪器的安装、调试、验收、日常分析,实验室管理等几个方面,分别作了介绍。  相似文献   
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