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121.
We have recently developed a new type of liquid junction-free reference electrode that is suited for fabrication of miniature ion sensor devices. The proposed reference electrode system employs a solvent-processible polymer membrane, and the best performance membrane so far is formulated with an aromatic type polyurethane,synthesized with 4,4'- methylenebis(phenyl isocyanate) and poly(tetramethylene ether glycol). 相似文献
122.
Durham等[1]曾利用Pt(黑)|lN HCl‖Ru(bipy)32+、MV2+、EDTA(pH=9)|Pt(网)电池模拟光解水析氢反应。但该装置的左、右二半电池中溶液的pH值相差9以上,相当于外加0.5V以上的偏压,因此,不能真实地模拟自发的光解水析氢过程。 相似文献
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Kyu Ho Van Jeong Park Sung Hwan Yoon Suk Ho Chung Min Suk Cha 《Proceedings of the Combustion Institute》2019,37(2):1997-2004
The oscillating lifted flame in a laminar nonpremixed nitrogen-diluted fuel jet is known to be a result of buoyancy, though the detailed physical mechanism of the initiation has not yet been properly addressed. We designed a systematic experiment to test the hypothesis that the oscillation is driven by competition between the positive buoyancy of flame and the negative buoyancy of a fuel stream heavier than the ambient air. The positive buoyancy was examined with various flame temperatures by changing fuel mole fraction, and the negative buoyancy was investigated with various fuel densities. The density of the coflow was also varied within a certain range by adding either helium or carbon dioxide to air, to study how it affected the positive and negative buoyancies at the same time. As a result, we found that the range of oscillation was well-correlated with the positive and the negative buoyancies; the former stabilized the oscillation while the latter triggered instability and became a source of the oscillation. Further measurements of the flow fields and OH radicals evidenced the important role of the negative buoyancy on the oscillation, detailing a periodic variation in the unburned flow velocity that affected the displacement of the flame. 相似文献
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Cha??Koren Ronan?VicquelinEmail author Olivier?Gicquel 《Flow, Turbulence and Combustion》2018,101(1):77-102
A multi-physics simulation combining large-eddy simulation, conjugate heat transfer and radiative heat transfer is used to predict the wall temperature field of a confined premixed swirling flame operating under atmospheric pressure. The combustion model accounts for the effect of enthalpy defect on the flame structure whose stabilization is here sensitive to the wall heat losses. The conjugate heat transfer is accounted for by solving the heat conduction within the combustor walls and with the Hybrid-Cell Neumann-Dirichlet coupling method, enabling to dynamically adapt the coupling period. The latter coupling procedure is enhanced to determine statistics (mean, RMS, \(\ldots \)) in a permanent regime accurately and efficiently thanks to an acceleration technique which is derived and validated. The exact radiative heat transfer equation is solved with an advanced Monte Carlo method with a local control of the statistical error. The coupled simulation is carried out with or without accounting for radiation. Excellent results for the wall temperature are achieved by the fully coupled simulation which are then further analyzed in terms of radiative effects, global energy budget and fluctuations of wall heat flux and temperature. 相似文献
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Wenjia Wang Xiaoyun Yang Guangcai Chang Pengfei An Kewen Cha Yuhui Dong Peng Liu 《Journal of synchrotron radiation》2017,24(4):781-786
A method to calibrate and stabilize the incident X‐ray energy for anomalous diffraction data collection is provided and has been successfully used at the single‐crystal diffraction beamline 1W2B at the Beijing Synchrotron Radiation Facilities. Employing a feedback loop to control the movement of the double‐crystal monochromator, this new method enables the incident X‐ray energy to be kept within a 0.2 eV range at the inflection point of the absorption edge. 相似文献
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