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Soybean cultivar selection for Bioregenerative Life Support Systems (BLSSs) – Hydroponic cultivation
R. Paradiso R. Buonomo V. De Micco G. Aronne M. Palermo G. Barbieri S. De Pascale 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2012
Four soybean cultivars (‘Atlantic’, ‘Cresir’, ‘Pr91m10’ and ‘Regir’), selected through a theoretical procedure as suitable for cultivation in BLSS, were evaluated in terms of growth and production. Germination percentage and Mean Germination Time (MGT) were measured. Plants were cultivated in a growth chamber equipped with a recirculating hydroponic system (Nutrient Film Technique). Cultivation was performed under controlled environmental conditions (12 h photoperiod, light intensity 350 μmol m−2 s−1, temperature regime 26/20 °C light/dark, relative humidity 65–75%). Fertigation was performed with a standard Hoagland solution, modified for soybean specific requirements, and EC and pH were kept at 2.0 dS m−1 and 5.5 respectively. 相似文献
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祁福雪 《沈阳航空工业学院学报》2010,27(6):68-70
杜甫一生创作了大量诗歌,今存一千四百余首。仅漂泊西南十一年间所创作的诗篇即占其作品总数的百分之七十以上。其西南诗不仅数量多,而且所表现出的深邃思想内涵和炉火纯青的艺术技巧,为我们展现了一位老而弥坚、不断追求的"诗圣"形象。在杜甫研究的领域内,本文第一次较为全面、深入地探讨了西南漂泊生涯与客寓意识对杜甫人生追求的影响,推动其后期乡国君民诗登上一个新的高度。 相似文献
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航天技术的发展与应用使在轨服务成为可能,由于各种限制因素的制约,服务航天器需要选择适当的时机,并在一定的时间范围内实施机动以提供在轨服务.提出并界定了机动窗口的概念,分析了机动窗口的制约因素,重点探讨了在机动能量制约下圆轨道之间的机动窗口计算问题.根据服务任务的紧急程度,分别研究了最省能量的漂移式机动窗口和节省时间的快速机动窗口.计算结果表明,共轨部署的服务航天器在能量有限、而时间不限的情况下,比其他部署方式有更多的机动时机,机动能量是制约机动窗口的关键因素. 相似文献
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分析了CFM56-7B型发动机在冬季高原多次发生航前第一次起动不成功的原因,并针对该故障提出了相关的维护建议,以供同行借鉴。 相似文献
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Roberta Paradiso Roberta Buonomo Mike A. Dixon Giancarlo Barbieri Stefania De Pascale 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
Soybean [Glycine max (L.) Merr.] is one of the plant species selected within the European Space Agency (ESA) Micro-Ecological Life Support System Alternative (MELiSSA) project for hydroponic cultivation in Biological Life Support Systems (BLSSs), because of the high nutritional value of seeds. Root symbiosis of soybean with Bradirhizobium japonicum contributes to plant nutrition in soil, providing ammonium through the bacterial fixation of atmospheric nitrogen. The aim of this study was to evaluate the effects of two hydroponic systems, Nutrient Film Technique (NFT) and cultivation on rockwool, and two nitrogen sources in the nutrient solution, nitrate (as Ca(NO3)2 and KNO3) and urea (CO(NH2)2), on root symbiosis, plant growth and seeds production of soybean. Plants of cultivar ‘OT8914’, inoculated with B. japonicum strain BUS-2, were grown in a growth chamber, under controlled environmental conditions. 相似文献
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Kingsley Chukwudi Okpala Chinasa Edith Ogbonna 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2018,61(7):1858-1872
The bulk association between ionospheric storms and geomagnetic storms has been studied. Hemispheric features of seasonal variation of ionospheric storms in the mid-latitude were also investigated. 188 intense geomagnetic storms (Dst ≤ 100 nT) that occurred during solar cycles 22 and 23 were considered, of which 143 were observed to be identified with an ionospheric storm. Individual ionospheric storms were identified as maximum deviations of the F2 layer peak electron density from quiet time values. Only ionospheric storms that could clearly be associated with the peak of a geomagnetic storm were considered. Data from two mid-latitude ionosonde stations; one in the northern hemisphere (i.e. Moscow) and the other in the southern hemisphere (Grahamstown) were used to study ionospheric conditions at the time of the individual geomagnetic storms. Results show hemispheric and latitudinal differences in the intensity and nature of ionospheric storms association with different types of geomagnetic storms. These results are significant for our present understanding of the mechanisms which drive the changes in electron density during different types of ionospheric storms. 相似文献
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研究了某型机载近程导航系统接收机的航向和下滑线信号因装备时间长引起电流漂移,从而导致引导飞机正常着陆的信号误差变大的具体原因,分析了着陆信号变换器的失效机理,给出了关键节点的理论推导过程和参考标准值,通过采取针对性的解决措施,从根本上提高飞机在着陆过程中的飞行安全性。 相似文献
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通过对不同粒径、不同湿度的赤泥起尘风速及起尘强度的风洞实验发现,对各种湿度的赤泥,都存在一临界粒径。当赤泥粒径小于该值时,起尘风速随粒径的减小而增大,而当粒径大于该值时,起尘风速随粒径的增大而增大。临界粒径大约为0.2mm,随湿度略有变化。临界粒径对应的起尘风速最小,它随湿度的增大而升高,其变化范围为2.5~3.0m/5,对应的起动摩擦速度介于0.17~0.20m/s。此外,当粒径小于0.1mm时,起尘风速随湿度的增大而减小,而当粒径大于0.2mm 以后,起尘风速随湿度的增大而增大。起尘强度实验表明,风速一定且大于4.7m/s,湿度小于15%时,起尘强度随湿度增大而减小,湿度大于15%时,起尘强度随湿度变化甚微。风速小于4.7m/s时,起尘强度基本不随湿度而变。湿度一定时,起尘强度随风速的增大而增大。文章还讨论了模拟实验的相似准则和定量换算问题。 相似文献