共查询到19条相似文献,搜索用时 125 毫秒
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为了实现氢同位素气体在线检测,利用气体低气压辉光放电性质,设计加工了氢同位素在线测定装置并建立了辉光放电原子光谱法在线测定氢同位素的分析方法。该装置由辉光放电管、激发光源、真空–微量进气系统、光谱仪及数据采集系统等部件组成。采用不同含量的系列氕氘气体作为标准气体,绘制标准工作曲线,建立了氢同位素在线检测分析方法,氕氘气体的检出限均为0.04%,氕浓度、氘浓度和氕氘浓度比测量的相对标准偏差分别为3.6%,5.2%和2.4%(n=6)。该分析装置性能稳定可靠,操作简单,可实现氢同位素气体在线检测。 相似文献
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A method for the analysis of gas mixtures containing both carbon monoxide and nitrogen, by using a single-focussing mass spectrometer, is described. It involves measurement of the mass spectrum of a gas sample before and after conversion of the carbon monoxide present into carbon dioxide by means of the Schütze catalyst. 相似文献
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Carole L. Walters 《Microchemical Journal》1982,27(1):116-123
The gas sample transfer apparatus, as shown in Fig. 1, was designed to facilitate the analysis of several carbon monoxide samples during a normal work day. With this apparatus, gas samples were accurately transferred from the Tedlar bags leak free through the system to the reaction flask. Changing from one gas concentration to another was greatly simplified by using the quick-connect fittings; gas volumes were readily calculated from direct readings taken from the differential pressure gauge.Tests were conducted to assess the performance of the PdCl2 method and the sampling system with various gas mixtures. The proposed PdCl2 method utilizing this particular sampling scheme is capable of successfully measuring carbon monoxide in nitrogen cylinder gas at levels of 0.1, 0.05, and 0.01% with expected average recoveries of 96, 96, and 93%, respectively. 相似文献
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Stanislav Pekárek 《Plasma Chemistry and Plasma Processing》2017,37(5):1313-1330
We investigated nitrogen monoxide, nitrogen dioxide and ozone generation for corona-like dielectric barrier discharge in a stationary magnetic field with airflow. The magnetic field was produced by the permanent magnet. We showed that nitrogen monoxide could be easily generated at relatively low voltages, by application of a magnetic field on the hollow needle to mesh with a dielectric barrier discharge. For higher voltages generation of nitrogen monoxide falls to zero, and generation of nitrogen dioxide and ozone with increasing voltage increases. We also demonstrated that simultaneous application of the magnetic field with airflow through the needle electrode affects the transition of the discharge from the high to the low voltage regime. This transition is accompanied by important changes in the production of nitrogen oxides and ozone. Changes in the discharge regime are reflected by changes in the voltage–current waveforms. The obtained results could be interesting for various biomedical applications or bacterial decontamination of surfaces. 相似文献
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Friedrich A. Lagler Michel O. Gerboles Annette Borowiak 《Accreditation and quality assurance》2007,12(1):30-38
A prototype of an automatic static volumetric method based on the injection of a pure compound by means of a loop instead
of a manual syringe was constructed, fitting for both laboratory use and field applications. The crucial point, the evaluation
of the loop volumes, was solved developing two techniques allowing traceability to SI units. Gas mixtures of nitrogen monoxide
(NO) in nitrogen in the 10−9 V/V range and carbon monoxide (CO) in air in the 10−6 V/V range were generated and successfully compared to other primary calibration techniques. Relative expanded uncertainties
(k=2) of 1.1% (compared to 0.8% of the manual static volumetric method [1]) for NO gas mixtures and 0.3% CO gas mixtures were estimated. 相似文献
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Liu Kun Zheng Zhenfeng Liu Shiting Hu Youyi 《Plasma Chemistry and Plasma Processing》2019,39(5):1255-1274
Plasma Chemistry and Plasma Processing - The chemical product behaviors of dielectric barrier discharge (DBD) in N2/O2 gas mixtures are investigated. Besides ozone mode and nitrogen oxides mode, a... 相似文献
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高灵敏度的脉冲氦离子化检测器分析混合气体中的Kr、Xe 总被引:1,自引:0,他引:1
使用高灵敏度的脉冲氦离子化检测器(PDHID)气相色谱法对Kr、Xe浓度进行定量分析,并通过采用反应床除去杂质气体或与Kr、Xe难以分离的干扰组分N2、CH4和CO等,可使最低检测限达到Kr为7.931×10^-8、Xe为7.186×10^-8.对Kr的测量相对偏差在2%以内,对Xe的测量相对偏差在6%以内. 相似文献
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Civis S Babánková D Cihelka J Sazama P Juha L 《The journal of physical chemistry. A》2008,112(31):7162-7169
Large-scale plasma was created in gas mixtures containing carbon monoxide by high-power laser-induced dielectric breakdown (LIDB). The composition of the mixtures used corresponded to a cometary and/or meteoritic impact into the Earth's early atmosphere. A multiple-centimeter-sized fireball was created by focusing a single 85 J, 450 ps near-infrared laser pulse into the center of a 15 L gas cell. The excited reaction intermediates that formed in various stages of the LIDB plasma chemical evolution were investigated by optical emission spectroscopy (OES) with temporal resolution. Special attention was paid to any OES signs of molecular ions. However, carbon monoxide cations were registered only if their production was enhanced by Penning ionization, i.e., excess He was added to the CO. The chemical consequences of laser-produced plasma generation in a CO-N 2-H 2O mixture were investigated using high resolution Fourier-transform infrared absorption spectroscopy (FTIR) and gas chromatography (GC). Several simple inorganic and organic compounds were identified in the reaction mixture exposed to ten laser sparks. H 2 (18)O was used to avoid possible contamination. The large laser spark triggered more complex reactivity originating in carbon monoxide than expected, when taking into account the strong triple bond of carbon monoxide causing typically inefficient dissociation of this molecule in electrical discharges. 相似文献
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The redox ability of isolated Mo5+ cations in model MoH-beta and MoH-ZSM-5 systems is studied byin situ ESR. The oxidation of reduced samples by nitrogen monoxide at 20°C proceeds much faster than oxidation by oxygen. The interaction
between Mo5+ ions and propene at 20°C results in the formation of a complex in which the oxidizability of Mo(V) by NO is substantially
enhanced. UV irradiation increases the oxidation rate for Mo5+ ions in HZSM-5 by nitrogen monoxide at 20°C, indicating the possibility for the photochemical activation of the process.
The step of active site reduction during the interaction of the samples with the H2 + NO + He gas mixtures of various compositions at 500°C is fast, and the dynamic equilibrium of the redox Mo(V) ai Mo(VI)
reaction is shifted to the left
Deceased. 相似文献
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A. V. Zosimov V. V. Lunin V. G. Samoilovich E. A. Abramovskaya Yu. A. Mankelevich A. Yu. Poroykov T. V. Rakhimova D. G. Voloshin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(8):1687-1692
The yield of ozone in barrier discharges in oxygen–nitrogen mixtures containing 0.001 to 40% of nitrogen is investigated experimentally. Phenomena of the nonstationarity of processes of ozone generation that differ from the known ozone-zero phenomenon (OZP) apparent in the reduced efficiency of ozone generation in very high purity oxygen at long periods (from hours to tens of hours) of ozonator operation are found. It is established that the characteristic times (from minutes to tens of minutes) of ozone attaining stationary values after changes in the discharge parameters indicate slow adjustment of the surface condition of insulators and thus the heterogeneous decay of ozone to more rapidly changing flows of neutral and charged particles from gas discharge plasma on the surfaces of dielectrics. The possibility of such a scenario is confirmed using a new analytical approach and numerical calculations of the plasma–chemical kinetics of N2/O2 mixtures presented in the accompanying theoretical study. 相似文献