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991.
本文进行了将国产早期填充柱气相色谱仪改装成高分辨裂解气相色谱仪的研究实验,实践结果证明该实验系统符合高分辨裂解气相色谱分析方法的要求。 相似文献
992.
During thermochemical conversion of biological material in a fluidized bed reactor the nutrients are remaining as dust in the product gas. Hot gas filtration represents a possibility to recover these minerals. The characteristics of this gas add up new technical tasks. The following article gives an account of long lasting experience of operation and optimization in a pilot plant. 相似文献
993.
《分离科学与技术》2012,47(3):297-301
Abstract Chromatography of 47 cations in 11 solvent systems has been performed on stannic molybdate ion exchange papers. Some difficult separations, e.g., Rb from Cs, Al-Be-Ga, and Tl-In, and specific separations of Ga, Au and Mg from numerous metal ions, have been achieved. R F values of some common metal ions on these papers have been compared with R F values of these cations on stannic tungstate and stannic phosphate papers. The preparation of papers is easy and the results are reproducible. 相似文献
994.
《分离科学与技术》2012,47(15):2065-2087
Abstract Mathematical equations have been formulated to predict the longitudinal concentration distribution in the case of instantaneous behavior of a continuous chromatographic system. Partial differential equations are initially obtained from mass balance on the differential element of column height. The formulated equations are solved by Lap lace transformation and the contour integration method. Two equations are obtained, one for the column section above the feed point and the second for the column section below the feed. Both of these equations give the concentration distribution along the appropriate section of the column. The model predicts the instantaneous and steady-state behavior of the continuous moving-bed chromatographic system. The model can also be used as a tool for the design of new continuous chromatographic columns. 相似文献
995.
An approximate analysis of gas absorption with instantaneous reaction in a liquid layer of finite thickness in plug flow is presented. An approximate solution to the enhancement factor for the case of unequal diffusivities between the dissolved gas and the liquid reactant has been derived and validated by numerical simulation. Depending on the diffusivity ratio of the liquid reactant to the dissolved gas (γ), the enhancement factor tends to be either lower or higher than the prediction of the classical enhancement factor equation based on the penetration theory (Ei,pen) at Fourier numbers typically larger than 0.1. An empirical correlation valid for all Fourier numbers is proposed to allow a quick estimation of the enhancement factor, which describes the prediction of the approximate solution and the simulation data with a relative error below 5 % under the investigated conditions (γ = 0.3–4, Ei,pen = 2–1000). 相似文献
996.
The oxygen volumetric mass transfer coefficient is a key parameter to characterize the performance of aerobic bioreactors. A novel rotating‐drum bioreactor (RDB) fitted with a sparger as proposed in a previous work has demonstrated its excellent gas‐liquid mass transfer performance. To provide primary information on the design and scale‐up of the novel RDB, effects of reactor configuration including the number and width of lifters and operation conditions such as rotational speed, aeration rate, and solid volume fraction on mass transfer performance were systematically investigated in a new medium‐sized RDB. Compared with the stirred bioreactor and traditional RDBs, this new RDB exhibits better mass transfer performance. Taking both operational and reactor configuration parameters into consideration, an empirical correlation to predict the volumetric mass transfer coefficient in this type of RDBs was proposed which is valuable for its design and scale‐up. 相似文献
997.
N. Tuning S. BachmannY. Bagaturia M. BlomL. Ceelie D. van EijkCh. Färber T. HaasF. Jansen T. KetelM. Merk I. MousA. Nawrot A. PellegrinoO. van Petten T. du PreeN. Serra E. SimioniT. Sluijk B. StoraciM. Szczekowski U. UwerE. Visser D. Wiedner 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,656(1):45-50
The LHCb Outer Tracker straw tubes have shown to suffer from gain loss after irradiation in the laboratory at moderate intensities. Under irradiation an insulating layer is formed on the anode wire. The ageing is caused by contamination of the counting gas due to outgassing of the plastifier di-isopropyl-naphthalene in araldite AY103-1 used at construction. This paper presents irradiation results with and without the plastifier, together with the mass spectra of the glue samples. In addition, the effects of wire heating and large currents are presented. 相似文献
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