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22.
目的分析控制力矩陀螺的微振动扰动特性。方法通过获取陀螺连接点对结构的扰振力输出、关键部位的微振动响应来获取产品的微振动扰动特性,通过隔振的方式对外部环境的干扰进行隔离,进而降低测试的背景噪声,通过运用高精度测试传感器来实现微小扰动力信号、加速度信号的测量,利用结构有限元法及单点激励多点响应的模态分析方法校核系统刚度,进而确定测试频率范围是否满足需求。结果可同时获得空间站控制力矩陀螺连接点处的输出扰振力、质心处的输出扰振力合力、合力矩以及关键部位的微振动响应,可有效隔离外部干扰,扰振力背景噪声的时域信号最大值可控制在0.07 N以内,RMS值在0.02 N以内,加速度信号的时域背景噪声最大值可控制在1.5 mg以内,RMS值在0.1 mg以内。可识别微小扰振信号,加速度传感器分辨率为5×10-5 grms,力传感器的测量分辨率为1×10-2 N,力矩测量分辨率小于1×10-2 N·m。测试频带在320 Hz以内。结论满足型号需求,并投入型号使用。 相似文献
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陈娟 《环境监测管理与技术》2002,14(5):28-28
在过硫酸钾消解-钼蓝比色法测定总磷中,当显色液吸光值超出校准曲线范围时,进行了显色液稀释后再行测定的试验,试验结果与水样稀释重新消解[测定所得结果作统计检验,两者间无显著性差异,稀释倍数最大不宜超过4倍。 相似文献
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色谱、光谱及联用技术在多农药残留检测中的应用 总被引:5,自引:4,他引:5
介绍了国内外多农药残留检测的发展状况,综述了色谱法、光谱法、色谱-质谱联用技术、色谱-光谱联用法、多维气相色谱技术的特点及在多农药残留检测中的应用,指出多农药残留检测在今后的农药残留检测中将占据主导地位. 相似文献
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Cariñanos P Sánchez-Mesa JA Prieto-Baena JC Lopez A Guerra F Moreno C Dominguez E Galan C 《Journal of environmental monitoring : JEM》2002,4(5):734-738
The aim of this study was to analyse the relationship between the distribution of hay-fever patients in the city of Córdoba, south-western Iberian Peninsula, and the specific atmospheric biological content originating from local sources. Four different districts were established in the metropolitan area of the city, according to vegetational and urbanistic characteristics. Air samples were taken in each area using portable Hirst-type samplers (Lanzoni VPPS 1000) and the spectrum of biological content was defined. Patients attending the Allergy Unit at Córdoba Teaching Hospital in 2000 with allergic rhinitis and/or asthma, and displaying a positive reaction to aeroallergen extracts, were distributed within the areas as a function of their district of residence. Aerobiological results revealed differences in pollen content between areas, in terms of both quantity and number of pollen types recorded. These differences were largely due to proximity to rural areas, prevalence of pollen from typically urban species and the possible effect of urban architecture as a barrier to the dispersal/ concentration of particles and other pollutants. Patients were not uniformly distributed within the city. The majority lived in districts in which pollen from rural species was mixed with pollen from ornamentals. Patients living in typically urban districts displayed a higher prevalence of allergy to pollen from ornamentals. It is concluded that a high degree of exposure to the same environment may influence the development of sensitisation to the particular pollen load associated with that area. 相似文献
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Li Ning Li Guangming Yao Zhenya Zhao Jianfu 《Frontiers of Environmental Science & Engineering in China》2007,1(2):190-195
Catalytic wet air oxidation (CWAO) is one of the most promising technologies for pollution abatement. Developing catalysts
with high activity and stability is crucial for the application of the CWAO process. The Mn/Ce complex oxide catalysts for
CWAO of high concentration phenol-containing wastewater were prepared by coprecipitation. The catalyst preparation conditions
were optimized by using an orthogonal layout method and single-factor experimental analysis. The Mn/Ce serial catalysts were
characterized by Brunauer-Emmett-Teller (BET) analysis and the metal cation leaching was measured by inductively coupled plasma
torch-atomic emission spectrometry (ICP-AES). The results show that the catalysts have high catalytic activities even at a
low temperature (80°C) and low oxygen partial pressure (0.5 MPa) in a batch reactor. The metallic ion leaching is comparatively
low (Mn<6.577 mg/L and Ce<0.6910 mg/L, respectively) in the CWAO process. The phenol, CODCr, and TOC removal efficiencies in the solution exceed 98.5% using the optimal catalyst (named CSP). The new catalyst would
have a promising application in CWAO treatment of high concentration organic wastewater.
Translated from Techniques and Equipment for Environmental Pollution Control, 2005, 6(2): 40–44 [译自: 环境污染治理技术与设备] 相似文献
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