Results 1 to 10 of about 1,093,094 (159)

基于NDIR技术的微量环保绝缘气体C₄F₇N检测

Gaoya dianqi
C4F7N混合气体由于其优异的绝缘性能和更低的温室效应被认为是一种优异的替代SF6的环保绝缘气体，C4F7N/CO2混合气体绝缘设备已被逐渐推广和使用。由于混合气体的绝缘性能与C4F7N的体积分数有关，通过对混合气体中微量C4F7N的检测，可以对C4F7N/CO2混合气体电气设备的绝缘状态进行有效评估。文中通过红外光谱平台，确定了C4F7N的红外光谱信息。通过对C4F7N体积分数为100~2 000 μL/L的C4F7N/CO2混合气体检测，确定了微量C4F7N的最佳检测波段 ...
刘伟, 刘子恩, 梁颂冰, 严进, 朱正宜, 张引   +5 more
doaj  

[Association between ambient personal temperature exposure and oxygen saturation during sleep in patients with chronic obstructive pulmonary disease]. [PDF]

Beijing Da Xue Xue Bao Yi Xue Ban
Zuo M, Zhang W, Chen B, Zhao C, Chen Y, He J, Guo X, Deng F.   +7 more
europepmc   +1 more source

[Determination of 16 organic ultraviolet absorbers in drinking water by solid phase extraction-ultra-high performance liquid chromatography-tandem mass spectrometry]. [PDF]

Se Pu
Wang Z, Zhao C, Ye BX, Chen YY.
europepmc   +1 more source

[Preparation of mesoporous covalent organic framework core-shell stationary phase and its application in the analysis of astragaloside Ⅳ content in <i>Astragalus</i>]. [PDF]

Se Pu
Zhao XY, Jin JY, Liu XJ, Yan LJ, Yang SY, Zhang ZW, Zhang LY, Wu RF.   +7 more
europepmc   +1 more source

温度对SF₆/CF₄混合气体尖板放电特性的影响

Gaoya dianqi
气体绝缘电气设备使用SF6/CF4混合气体可以避免SF6气体液化，适合在极寒地区应用。为获得设备内部存在尖端放电缺陷时SF6/CF4混合气体的绝缘性能受温度的影响，采用尖板电极模拟缺陷尖端放电，开展SF6/CF4混合气体在0.1~0.7 MPa气压范围和-50~20 ℃温度范围的工频放电实验。结果表明，不同温度下SF6/CF4混合气体的击穿电压随气压升高均出现先升高—再降低—再升高的驼峰趋势；但随着温度降低，驼峰峰值处的击穿电压随温度降低出现降低趋势，而在非驼峰峰值处的击穿电压随温度降低而基本不变 ...
陈远东, 郑宇, 孟辉, 沈腾达, 梁建, 周文俊   +5 more
doaj  

[Determination of 13 prohibited alkaloids in essential oil-based cosmetics by ultra performance liquid chromatography-tandem mass spectrometry combining QuEChERS purification]. [PDF]

Se Pu
Liu Z, Wang YM, Pan JB, Zong LL, Song YH, Sun XJ, Chen HY.   +6 more
europepmc   +1 more source

[Determination of 22 organophosphates and their metabolites and 11 phthalate metabolites in human whole blood by ultra performance liquid chromatography-tandem mass spectrometry]. [PDF]

Se Pu
Shi FY, Xu HY, Li JH, Xu MY.
europepmc   +1 more source

C₄F₇N/CO₂混合气体湿度检测技术研究

Gaoya dianqi
电气设备中C4F7N/CO2混合绝缘气体的湿度水平影响气体的绝缘性能，定期检测湿度是日常运维工作之一。文中研究采用变电站日常运维中常规的冷镜式露点仪和阻容式湿度计对不同湿度的C4F7N/CO2混合绝缘气体进行检测，实验表明上述常规湿度检测仪器均不能直接应用于C4F7N/CO2混合气体的湿度检测。文中将上述冷镜式露点仪进行技术改造后，采用标准湿度的C4F7N/CO2混合气体对其进行准确度实验，结果表明，改造后的冷镜式露点仪的露点测量误差不超过±0.2 ℃，且在C4F7N比例不超过12 ...
谢成, 邵先军, 张伟, 王鑫, 丁五行, 何毅帆   +5 more
doaj  

[Determination of atmospheric intermediate volatility organic compounds with thermal desorption-flow modulator comprehensive two-dimensional gas chromatography- time-of-flight mass spectrometry]. [PDF]

Se Pu
Wang R, Li YJ, Wang JH, Ma CW, Jiang JK.
europepmc   +1 more source

[Determination of seven tire antioxidants and their quinone oxidation products in fine particulate matter by high performance liquid chromatography-tandem mass spectrometry]. [PDF]

Se Pu
Liu F, Tang BB, Wu LY, Song LX, Zhang M, He M.   +5 more
europepmc   +1 more source