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21.
李春利  安乐  李浩  李彤  齐颖  程永辉 《化工进展》2020,39(11):4625-4631
二氯甲烷作为溶剂广泛应用于制药行业,其挥发性废气对人类健康和大气环境的危害极大。本文采用生物滴滤床对某制药厂浓度范围在0.02~2g/m3的二氯甲烷废气进行了为期132天的中试规模实验。在适宜的停留时间、温度、喷淋量和pH等实验条件下,控制适当的进气浓度可得到高效去除效率并且废气出口浓度达标。实验揭示了生物膜内生物降解是过程的限制因素,结果表明,在喷淋量为1200L/h、进气浓度范围为0.45~0.65g/m3时该生物系统去除效率最高可达98.9%,最大去除负荷可达ECmax=155.25g/(m3·h)。随着进气浓度的增加,去除负荷随之增大,而去除效率下降,废气出口浓度超标,表明生物滴滤系统已处于反应控制。此外,间歇实验表明,该生物系统具有良好的稳定性。指出生物滴滤床的设计、运行取决于当地的二氯甲烷废气排放标准。  相似文献   
22.
范俊  庞丽萍  刘道锦  张行  赵淼 《化工学报》2020,71(z2):80-84
现代军用直升机经常执行特殊飞行任务,其机载电子设备具有功率大、瞬间振荡、高热通量等特点,使得环控系统的冷却需求呈指数上升趋势,进而制约着直升机的巡航功能和战斗性能的提升。针对直升机机载大功率电子设备的冷却需求,结合制冷剂、冷却液循环等子系统,搭建地面稳态试验台,针对蒸发器、冷凝器等关键部件进行了地面稳态试验。研究过程采用仿真与试验相结合的方法,开展了制冷循环中蒸发器、冷凝器等关键部件稳态仿真计算,且完成了蒸发器、冷凝器的换热性能试验研究,对所建立的仿真模型进行了有效性校核与参数修正。上述研究可为后续直升机液冷/蒸发制冷系统的关键部件设计提供一定的参考。  相似文献   
23.
The high proportion of seed coat of legume lupins results in big milling lose during kernel flour production, though the seed coat could be value-added as human food. The physicochemical and nutritional properties and antioxidant capacities of seed coats of six Australian sweet lupin cultivars grown at two locations were evaluated. Results showed that genotype, environment and their interaction were significant for seed coat percentage, proximate composition, dietary fibre content, polyphenols and antioxidant capacities. Strong correlations between seed coat lightness and polyphenol content were found. A comparison using multivariate analysis of the seed coat properties showed clear separation based on growing sites. This study indicates the enormous potential of Australian sweet lupin seed coat as an ‘antioxidant dietary fibre’ food source. The results could also benefit to breed varieties with desirable levels of nutrients and phytochemicals.  相似文献   
24.
This study investigated the effect of contrast in neutral-, warm-, and cool-colored spaces on spatial memory. Spatial memory was measured in terms of architectural scale and recollection of architectural elements and furniture. Participants (N = 114) viewed a short virtual simulation video of a residential studio and were asked to sketch a map of the architectural elements on distributed grid paper. Spatial memory was measured in terms of scale, and item recall rate. Contrast and hue had no significant effect on the memorization of proportional scale. However, high-contrast schemes allowed for a significantly higher recollection of architectural elements than low-contrast schemes. In comparing the effect of hues, a significant difference was seen in recalling detailed furniture and lighting items. Participants reported significantly better spatial memory of neutral and warm color schemes than of cool color schemes. There was no interaction effect between contrast and hue in the color combinations. These results can be applied in the design of color schemes for architectural spaces requiring enhanced spatial cognition and memory.  相似文献   
25.
载人航天器环热控一体化仿真分析   总被引:1,自引:0,他引:1       下载免费PDF全文
齐玢  段希希  阿嵘  江泓升 《化工学报》2020,71(z1):300-306
采用系统建模及仿真方法搭建了一种典型载人航天器环热控一体化系统模型,分析了系统的性能。针对3人7天载人飞行工况开展了仿真分析,结果表明,经过合理设计,该系统可将舱内温湿度、压力、氧分压等参数控制在航天医学指标要求范围内。环热控系统仿真结果较好地预测了系统工作过程,显示了主要参数的变化情况,结果合理,验证了仿真方法、系统仿真模型的正确性。通过控制流体回路外回路旁通阀门开度,可准确控制外回路控温点温度,保证舱内温湿度在合理范围之内。此外,外回路控温点的设定会对环热控系统状态带来影响,通过合理设计外回路控温点,可保证舱内温湿度满足航天医学指标要求。  相似文献   
26.
许继军  吴志广 《人民长江》2020,51(1):124-128
针对长江水资源开发保护中存在的主要问题,以及新时代长江经济带发展和长江大保护背景下面临的新要求,展开了专项分析研究。研究结果表明:正确把握长江水资源开发保护与水环境治理及经济社会发展之间的关系,是协调长江经济带发展与长江大保护的关键所在。根据研究结果,提出了应当以水环境改善为突破点的长江水资源、水环境、水生态以及水灾害等四水共治的思路;同时还提出了管理与技术、经济与法律及文化等多种手段相结合的针对长江水资源开发保护的对策和建议。  相似文献   
27.
《Ceramics International》2020,46(11):19121-19126
We examined the magnetic, structural, and chemical properties of CoFe2O4 films deposited on Al2O3 substrates using RF-magnetron sputtering under Ar and Ar + O2 environments. Perpendicular magnetic anisotropy with large magnetization was observed in the case of the film deposited under the Ar + O2 environment. However, no significant anisotropy appeared in the film deposited under the Ar environment. Interestingly, depth-dependent X-ray photoelectron spectra showed nearly identical stoichiometric ratios of Co/Fe and oxygen vacancies regardless of the deposition environment. Structurally, high-quality crystallinity with in-plane compressive strain, and lower surface and interfacial roughness were induced in the film deposited under the Ar + O2 environment. Cross-sectional transmission electron microscopy and X-ray reflectivity measurements showed that oxygen not only suppressed the deposition rate but also increased the electron density of the film, resulting in better crystallinity. Hence, the presence of oxygen during deposition should be considered as one of the essential parameters for improving the structural and magnetic properties of ferrite films.  相似文献   
28.
磁性纳米材料具有较强的化学稳定性、可再生回收、良好的吸附性能和易于分离等优点,在去除水溶液中的铀酰离子方面有广泛的应用前景。然而,磁性纳米材料也存在易团聚、易氧化等不足,通过表面修饰或改性等方法可改善其不足,提高其对废水中铀酰离子的去除能力,改善其吸附效果。本文通过总结近年来的相关研究资料,概括了磁性纳米材料的种类,归纳总结并比较了不同种类磁性纳米材料对含铀废水的去除能力及优势与不足,探讨了磁性纳米材料在含铀废水处理中的应用并对其机理进行了分析,阐述了磁性纳米材料去除溶液中铀酰离子的影响因素,简述了目前磁性纳米材料在处理含铀废水中有待解决的问题,并对其在分离放射性元素方面的应用前景进行了展望。  相似文献   
29.
The level of oleic acid is an important parameter in determining seed nutritional quality and oil stability. The level of oleic acid in peanut is genetically controlled by a pair of fatty acid desaturase genes (FAD2A and FAD2B), but the environmental conditions of the production sites can also have a significant effect. To investigate the effect of gene and environment interaction, 45 accessions were grown at three locations for 2 years. Environmental data were collected; individual plants were genotyped with functional SNP markers from FAD2A and FAD2B; and seed level of oleic acid was determined by gas chromatography. Three FAD2A/FAD2B genotypes (448G/no insertion 442A, 448A/no insertion 442A, and 448A/insertion 442A) were identified and designated as G/W, A/W, and A/A, respectively. A/A genotype averaged the highest level of oleic acid (80.0%), followed by A/W (56.0%), and then G/W (40.7%). Analysis of gene and environment interaction revealed that oleic acid phenotype plasticity could be explained by the interaction of FAD2 genotype and photothermal time, which quantified environmental conditions. The A/W genotype was the most sensitive to photothermal time changes. The oleic acid plasticity revealed in this study would be useful for breeders, farmers, and product processors.  相似文献   
30.
The influences of two types of heat-treatments on the corrosion behavior of 316L SS in the simulated cathodic environment of PEMFC, are investigated using potentiodynamic curve, electrochemical impedance spectroscopy (EIS), Mott-Schottky plot and auger electron spectroscopy (AES), respectively. The results show that 316L SS is in the passive state within the potential region from −0.1VSCE to 0.8VSCE in the simulated cathodic environment of PEMFC, and a passive film can be formed on 316L SS. The passivity of 316L SS in the simulated cathodic environment of PEMFC firstly increases and then degrades with the increased solid solution temperature or time, and the best passivity corresponds to the solid solution temperature at 1050 °C for 40 min among other solid solution treatments. While 316L SS heat-treated with the solid solution treatment at 1050 °C for 40 min plus aging treatment at 900 °C for 4 h, also has the best passivity in the same solution among other solid solution plus aging treatments. The best corrosion protection, lowest donor density and the highest thickness of the passive film corresponding to the solid solution temperature at 1050 °C for 40 min among other solid solution or solid solution plus aging heat treatments, and this treatment is mostly suitable for improving the anti-corrosion property of 316L SS in the simulated cathodic environment of proton exchange membrane fuel cell (PEMFC).  相似文献   
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