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991.
M. Yamashita K. Tomita-Yokotani H. Hashimoto N. Sawaki M. Notoya 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
The treatment of sodium, Na, and potassium, K, presents a challenge in space agriculture material recycling, as humans require Na and plants cannot grow at high Na concentrations. Hence, we are proposing the use of marine macro-algae to harvest K and other minerals from composted human waste. Ulva was selected for this feasibility study, since it tolerates a wide range of salinity levels. Growth capability of Ulva was examined under various total salinity levels and proportions of Na and K in the incubation medium. A homeostatic feature of Ulva was found in its intra-cellular concentration of Na and K, and in the intra-cellular ratio between Na and K (at 0.58 ± 0.30, lower than that of human metabolic waste). Intracellular concentration of K in Ulva is 20 times higher than seawater. Because of these characteristics, Ulva is a good candidate species for space agriculture. 相似文献
992.
S.S. Kouris K.V. Polimeris L. Ciraolo D.N. Fotiadis 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
Several years of hourly daily GPS measurements of the vertical total electron content (TEC) and of the equivalent slab thickness made at different European locations are analysed by using the linear regression technique to demonstrate the response of these two ionospheric parameters to seasonal variations. It is found that both TEC and slab thickness are highly correlated with season. Analytical relationships are determined expressing the seasonal dependence of the vertical TEC and of the equivalent slab thickness as a function of the seasonal parameter cos χ at noon in each location. 相似文献
993.
S. Ushakova A. Tikhomirov V. Shikhov Yu. Kudenko O. Anischenko J.-B. Gros Ch. Lasseur 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
The purpose of this work was to study the full-scale potential use of human mineralized waste (feces and urine) as a source of mineral elements for plant cultivation in a biological life support system (BLSS). Plants that are potential candidates for a photosynthesizing link were grown on a neutral solution containing human mineralized waste. Spring wheat Triticum aestivum L., peas Pisum sativum L. Ambrosia cultivar and leaf lettuce Lactuca sativa L., Vitaminny variety, were used. The plants were grown hydroponically on expanded clay aggregates in a vegetation chamber in constant environmental conditions. During plant growth, a determined amount of human mineralized waste was added daily to the nutrient solution. The nutrient solution remained unchanged throughout the vegetation period. Estimated plant requirements for macro-elements were based on a total biological productivity of 0.04 kg day−1 m−2. As the plant requirements for potassium exceeded the potassium content of human waste, a water extract of wheat straw containing the required amount of potassium was added to the nutrient solution. The Knop’s solution was used in the control experiments. 相似文献
994.
A.L. Mishev J.N. Stamenov I.I. Angelov N.O. Ahababian I.N. Kirov E.S. Malamova 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2009
We review the main activities carried out at Moussala peak (2925 m above sea level, 42°11′N, 23°35′E) station in Bulgaria, connected with cosmic ray investigations during the last five decades. Several important results obtained at the station are reported. The detector design and corresponding methodological studies of the presently operational devices are shown as well, precisely the Cherenkov light telescope, lead free neutron monitor and muon telescope. The scientific potential of the existing complex is discussed. 相似文献
995.
本文结合股份合作制企业的特点,系统的分析了股份合作制企业的劳动法律关系的特殊性和这些特殊性产生的根源。文章对实践中股份合作制企业在处理劳动关系的过程中经常出现的问题进行了分析,并且提出了解决问题的建议和思考。 相似文献
996.
Yann Alibert Christoph Mordasini Olivier Mousis Willy Benz 《Space Science Reviews》2005,116(1-2):77-95
We present models of giant planet formation, taking into account migration and disk viscous evolution. We show that migration
can significantly reduce the formation timescale bringing it in good agreement with typical observed disk lifetimes. We then
present a model that produces a planet whose current location, core mass and total mass are comparable with the one of Jupiter.
For this model, we calculate the enrichments in volatiles and compare them with the one measured by the Galileo probe. We
show that our models can reproduce both the measured atmosphere enrichments and the constraints derived by Guillot et al. (2004), if we assume the accretion of planetesimals with ices/rocks ratio equal to 4, and that a substantial amount of CO2 was present in vapor phase in the solar nebula, in agreement with ISM measurements. 相似文献
997.
某型飞机机身合拢总装型架,在设计上采用了先进制造技术。型架上装有目前国际先进的光学坐标系统,型架地基采用整体框架式底盘。型架结构为分散式。按飞机飞行状态在型架中摆放,并由上方起吊形式下架。本文简要介绍了该型架的设计、制造情况及效果。 相似文献
998.
999.
提出一种全新的飞行状态控制的实现途径———无舵飞行姿态控制,使飞机具有更优的飞控品质,并有利于气动外形和结构的优化。本文介绍了无舵飞行控制原理、飞控驱动装置控制功率需求的计算及确定方法等。 相似文献
1000.
介绍了利用模型表面的压力测量值经计算求出来流静压的方法和试验结果。文中涉及的计算方法为多元回归法,对试验所得压力数据进行处理,可拟合出多个不同参变量下的静压P∞的多元方程,从中选取一组较精确的作为计算公式进行验证试验,结果表明采用该方法测量静压具有较高的精度。 相似文献