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101.
Ming Li Dawei Hu Hong Liu Enzhu Hu Beizhen Xie Ling Tong 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
It is the primary task for a bioregenerative life support system (BLSS) to maintain the stable concentrations of CO2 and O2. However, these concentrations could fluctuate based on various factors, such as the imbalance between respiration/assimilation quotients of the heterotrophic and autotrophic components. They can even be out of balance through catastrophic failure of higher plants in the emergency conditions. In this study, the feasibility of using unicellular Chlorella vulgaris of typically rapid growth as both “compensatory system” and “regulator” to control the balance of CO2 and O2 was analyzed in a closed ecosystem. For this purpose, a small closed ecosystem called integrative experimental system (IES) was established in our laboratory where we have been conducting multi-biological life support system experiments (MLSSE). The IES consists of a closed integrative cultivating system (CICS) and a plate photo-bioreactor. Four volunteers participated in the study for gas exchange by periodical breathing through a tube connected with the CICS. The plate photo-bioreactor was used to cultivate C. vulgaris. Results showed that the culture of C. vulgaris could be used in a situation of catastrophic failure of higher plant under the emergencies. And the productivity could recover itself to the original state in 3 to 5 days to protect the system till the higher plant was renewed. Besides, C. vulgaris could grow well and the productivity could be affected by the light intensity which could help to keep the balance of CO2 and O2 in the IES efficiently. Thus, C. vulgaris could be included in the design of a BLSS as a “compensatory system” in the emergency contingency and a “regulator” during the normal maintenance. 相似文献
102.
本文主要阐述了一台研究旋转涡轮叶片或其他类似旋转部件冷却系统换热的实验设备,并介绍相应的实验手段和初步实验结果。 本实验可模拟气流平行于旋转轴方向的流动和气流垂直于旋转轴方向向外流及向内流等三种情况,基本上概括了冷却系统的全貌。故能满足旋转部件冷却系统换热的实验要求,试验结果是令人满意的,为旋转情况下的换热研究开辟了新路。 相似文献
103.
层合阻尼薄板之各向异性参数对损耗因子的影响分析 总被引:2,自引:0,他引:2
运用各向异性层合阻尼结构理论分析方法和正交试验等分析方法。着重考察了各层纤维铺设角度。纵、横剪切模量和纵、横拉伸模量等各向异性参数对各向异性层合阻尼薄板阻尼性能参数——损耗因子的影响。结果表明:各向异性参数在不同的模态下对层合阻尼薄板损耗因子的影响力不同,其中。各向异性层纤维铺设角度的影响较为复杂。其影响力在不同层合阻尼结构、不同的模态下差异较大;而纵、横剪切模量、纵、横拉伸模量的影响力随着模态的升高逐渐增大。此外,通过对各向异性参数的变化影响进一步分析表明:各向异性参数的变化影响各有特点,具有结构优化的潜能。 相似文献
104.
高超声速边界层转捩控制一直是空气动力学研究的热点。粗糙元延迟边界层转捩作为近些年才开始研究的内容,目前仍有诸多现象与机理尚未探究清楚。借助于华中科技大学Φ0.25 m Ma6 Ludwieg管风洞,本文研究了不同位置单粗糙元、多粗糙元与在不同来流情况下粗糙元对边界层转捩以及第二模态不稳定波发展的影响。风洞实验使用PCB132系列高频压力传感器获取尖锥壁面压力脉动信息,通过傅里叶积分变换与互相关分析获取压力脉动功率谱密度与第二模态不稳定波传播速度,对PSD数据计算获取第二模态不稳定波增长率。结果表明,当第二模态不稳定波经过粗糙元时,不稳定波幅值会有明显的减小,但其频段不稳定波的增长率会增大并最终导致转捩的结束点被提前。同时,粗糙元对第二模态不稳定波传播速度无明显影响。 相似文献
105.
对在EXCO溶液中预腐蚀后的LC4CS光滑试件和缺口试件进行疲劳试验,得到不同预腐蚀时间的S-N曲线及预腐蚀疲劳缺口系数。通过分析腐蚀过程,阐述了腐蚀对疲劳缺口系数的影响机理,建立了描述预腐蚀疲劳缺口系数的两参数模型,并进行了试验验证。结果表明:LC4CS材料的疲劳缺口系数随预腐蚀时间呈现出先降后升的变化趋势,其拐点出现在剥蚀开始阶段。 相似文献
106.
107.
通过理论分析和实验验证对多层带有微结构的硅硅直接键合技术进行了研究.采用的硅片表面活化处理方法是亲水湿法,采用的键合工艺流程是先将硅片在键合机中进行预键合,再使用退火炉进行高温退火.其中预键合参数对多层键合成功与否起到决定性的作用,为节约实验时间,针对3个主要预键合参数(温度、压力、时间)的选取进行了详细的正交实验分析.使用项目组自制的硅硅键合分析软件对键合片的红外图像进行处理分析,计算键合率.采用实验得到的最佳预键合工艺参数,多层键合的键合率达到了86.6527%. 相似文献
108.
F.C. Wasiak A. Luspay-Kuti W.D.D.P. Welivitiya L.A. Roe V.F. Chevrier D.G. Blackburn T. Cornet 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2013
As a result of measurements acquired by the Cassini–Huygens mission of Titan’s near surface atmospheric composition and temperature, Titan conditions can now be simulated in the laboratory and samples can subsequently be subjected to those conditions. Titan demonstrates an active hydrological-like cycle with its thick atmosphere, dynamic clouds, polar lakes of methane and ethane, moist regolith, and extensive fluvial erosive features. Unlike Earth, Titan’s hydrological-like cycle likely involves several constituents, primarily methane and ethane. Here the properties of a new Titan simulation facility are presented, including conceptual methodology, design, implementation, and performance results. The chamber maintains Titan’s surface temperature and pressure, and the sample cryogenic liquids undergoing experimentation are condensed within the chamber itself. During the experiments, the evaporation rates of the sample liquids are directly determined by continually measuring mass. Constituents are analyzed utilizing a Fourier Transform Infrared Spectroscopy (FTIR), and vapor concentrations are determined using a gas chromatograph fitted with a Flame Ionization Detector (FID). All pertinent data is logged via computer. Under laboratory conditions, the direct measurements of the evaporation rates of methane, ethane, and mixtures thereof can be achieved. Among the processes to be studied are the effects of regolith on transport from the subsurface to the atmosphere, the freezing point depression effects of dissolved nitrogen, and the solubility of various relevant organic compounds. 相似文献
109.
介绍“EDA”软件EWB的功能特点,探讨将其用于虚拟电工实验的可行性和优越性。 相似文献
110.