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大型综合室内亲子乐园属于高大空间,设有游乐设施和游戏的特殊性使得对空间的舒适性要求一致,但是送风气流遇阻严重,室内存在较多气流死角,影响室内空气质量和儿童健康。因此其空调设计不仅需要考虑温度、风速的空间均匀度,还要考虑各点的空气龄和PMV-PPD指标。以天津某亲子乐园为研究对象,利用scSTREAM软件对适用于该房间的辐射供冷加新风、置换通风、混合通风三种空调方式的送风效果进行数值模拟分析,从流场的均匀性、人员的热舒适性等方面对模拟结果进行探讨,研究结果表明辐射供冷加新风方式的空间均匀性和PMV指标最佳,混合通风方式的空气龄最小。 相似文献
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《Calphad》2021
The present work illustrates the effect of quasi-hydrostatic pressure on the positions and widths of the homogeneity ranges of the intermetallic phases TiFe and TiFe2 at high temperatures. The experiments were performed with Ti–Fe diffusion couples that were heat treated in a multi-anvil press at 2.5 GPa. The solubility limits of the phases were derived from the concentration profiles that were measured using electron probe microanalysis. It was found that the homogeneity ranges of TiFe and TiFe2 extend to higher titanium concentrations, if the pressure is applied. The positions of the phase boundaries of the intermetallics on the iron-rich side are not affected by the pressure. The accuracy of the experimental data including the homogeneity ranges and temperatures was verified by comparing the homogeneity ranges of β-Ti(Fe), α/δ-Fe(Ti) and γ-Fe measured in this study with the homogeneity ranges taken from literature. The pressure was calibrated using the pressure-induced phase transitions of bismuth. 相似文献
5.
Jialong Tian M. Babar Shahzad Wei Wang Lichang Yin Zhouhua Jiang Ke Yang 《材料科学技术学报》2018,34(9):1671-1675
The effect of Co addition on the formation of Ni-Ti clusters in maraging stainless steel was studied by three dimensional atom probe (3DAP) and first-principles calculation. The cluster analysis based on the maximum separation approach showed an increase in size but a decrease in density of Ni-Ti clusters with increasing the Co content. The first-principles calculation indicated weaker Co-Ni (Co-Ti) interactions than Co-Ti (Fe-Ti) interactions, which should be the essential reason for the change of distribution characteristics of Ni-Ti clusters in bcc Fe caused by Co addition. 相似文献
6.
Patrick D. Sullivan Mark J. Rood Katherine D. Dombrowski K. James Hay 《Canadian Metallurgical Quarterly》2004,130(3):258-267
Activated-carbon-fiber cloth (ACFC) is an alternative adsorbent to granular activated carbon (GAC) for removing and recovering organic vapors from gas streams. Electrothermal desorption (ED) of ACFC provides rapid regeneration while requiring less energy compared to traditional regeneration techniques used with GAC. This paper provides proof-of-concept results from a bench-scale ACFC adsorption system. The automated system captured 1,000 ppmv of hazardous air pollutants/volatile organic compounds (HAPs/VOCs) from air streams and demonstrated the use of ED, using ac voltage, to recover the HAP/VOC as a pure liquid. The desorbed HAP/VOC condensed onto the inner walls of the adsorber and was collected at the bottom of the vessel, without the use of ancillary cooling. Seventy percent of the HAP/VOC was collected per cycle as condensate, with the balance being retained in the regenerated adsorber or recycled to the second adsorber. ED with in-vessel condensation results in minimal N2 consumption and short regeneration cycle times allowing the process to be cost competitive with conventional GAC-based adsorption processes. This technology extends the application of carbon adsorption systems to situations that were previously economically and physically impractical. 相似文献
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P. G. Muzykov Y. I. Khlebnikov S. V. Regula Y. Gao T. S. Sudarshan 《Journal of Electronic Materials》2003,32(6):505-510
To establish fast, nondestructive, and inexpensive methods for resistivity measurements of SiC wafers, different resistivity-measurement
techniques were tested for characterization of semi-insulating SiC wafers, namely, the four-point probe method with removable
graphite contacts, the van der Pauw method with annealed metal and diffused contacts, the current-voltage (I-V) technique,
and the contactless resistivity-measurement method. Comparison of different techniques is presented. The resistivity values
of the semi-insulating SiC wafer measured using different techniques agree fairly well. As a result, application of removable
graphite contacts is proposed for fast and nondestructive resistivity measurement of SiC wafers using the four-point probe
method. High-temperature van der Pauw and room-temperature Hall characterization for the tested semi-insulating SiC wafer
was also obtained and reported in this work. 相似文献
9.
A vacuum-annealed La0.6Ca0.4CoO3−x was consecutively oxygenated in air at temperatures decreasing from 800 to 100 °C, and its electrocatalytic activities for oxygen reduction and evolution were then measured as a function of the oxygenation temperature. The valence of Co cation, changing between +2 and +3, was found susceptible to annealing either in vacuum or air. The catalytic activities initially decrease monotonically as the oxygenation temperature was decreased from 800 to 300 °C, as a result of increasing oxygen content, and then rise abruptly with the oxygen reduction activity reaching a maximum at 200 °C and the oxidation activity at 150 °C. X-ray photoelectron spectroscopy analysis indicated that the enhancements by the low-temperature oxygenation involved increased OH coverage and less charged cations at surface. The results clearly reveal the importance of the post-calcination annealing process for optimizing the performance of La0.6Ca0.4CoO3−x in air electrode applications. 相似文献
10.
通过广西水电南宁地质勘探基础工程处推行职工持股的思路,结合广西水利施工企业目前的具体情况, 就如何推行职工持股进行探讨,并提出建议及看法。 相似文献