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2009 1

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仿刺参 1

体腔液 1

吞噬细胞 1

调理素样分子 1

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Gear fault diagnosis using gear meshing stiffness identified by gearbox housing vibration signals

《机械工程前沿（英文）》 2022年第17卷第4期 doi: 10.1007/s11465-022-0713-3

摘要： Gearbox fault diagnosis based on vibration sensing has drawn much attention for a long time. For highly integrated complicated mechanical systems, the intercoupling of structure transfer paths results in a great reduction or even change of signal characteristics during the process of original vibration transmission. Therefore, using gearbox housing vibration signal to identify gear meshing excitation signal is of great significance to eliminate the influence of structure transfer paths, but accompanied by huge scientific challenges. This paper establishes an analytical mathematical description of the whole transfer process from gear meshing excitation to housing vibration. The gear meshing stiffness (GMS) identification approach is proposed by using housing vibration signals for two stages of inversion based on the mathematical description. Specifically, the linear system equations of transfer path analysis are first inverted to identify the bearing dynamic forces. Then the dynamic differential equations are inverted to identify the GMS. Numerical simulation and experimental results demonstrate the proposed method can realize gear fault diagnosis better than the original housing vibration signal and has the potential to be generalized to other speeds and loads. Some interesting properties are discovered in the identified GMS spectra, and the results also validate the rationality of using meshing stiffness to describe the actual gear meshing process. The identified GMS has a clear physical meaning and is thus very useful for fault diagnosis of the complicated equipment.

关键词： gearbox fault diagnosis meshing stiffness identification transfer path signal processing

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Fenton process for degradation of selected chlorinated aliphatic hydrocarbons exemplified by trichloroethylene, 1,1-dichloroethylene and chloroform

QIANG Zhimin, BEN Weiwei, HUANG Chin-Pao

《环境科学与工程前沿（英文）》 2008年第2卷第4期页码 397-409 doi: 10.1007/s11783-008-0074-0

摘要： The degradation of selected chlorinated aliphatic hydrocarbons (CAHs) exemplified by trichloroethylene (TCE), 1,1-dichloroethylene (DCE), and chloroform (CF) was investigated with Fenton oxidation process. The results indicate that the degradation rate was primarily affected by the chemical structures of organic contaminants. Hydroxyl radicals (OH) preferred to attack the organic contaminants with an electron-rich structure such as chlorinated alkenes (i.e., TCE and DCE). The dosing mode of Fenton’s reagent, particularly of Fe, significantly affected the degradation efficiency of studied organic compound. A new “time-squared” kinetic model, = exp(-), was developed to express the degradation kinetics of selected CAHs. This model was applicable to TCE and DCE, but inapplicable to CF due to their varied reaction rate constants towards OH. Chloride release was monitored to examine the degree of dechlorination during the oxidation of selected CAHs. TCE was more easily dechlorinated than DCE and CF. Dichloroacetic acid (DCAA) was identified as the major reaction intermediate in the oxidation of TCE, which could be completely removed as the reaction proceeded. No reaction intermediates or byproducts were identified in the oxidation of DCE and CF. Based on the identified intermediate, the reaction mechanism of TCE with Fenton’s reagent was proposed.

关键词： identified 1 1-dichloroethylene kinetic Dichloroacetic Chloride

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在仿刺参体腔液中发现新的调理素样分子

麦康森,孟繁伊,马洪明,张文兵

《中国工程科学》 2009年第11卷第10期页码 108-114

摘要：

通过研究发现，仿刺参体腔液中存在一种新的调理素样分子。通过SDS-PAGE，凝胶过滤层析，质谱分析等方法进行蛋白质的纯化和分析，采用荧光显微镜观察吞噬细胞对酵母细胞的吞噬作用，发现一种分子量约为18 kDa的分子可以结合到酵母细胞表面，并可以增强吞噬细胞的吞噬作用。推测这种分子是无脊椎动物调理素样分子中的新成员。同时也发现，虽然调理素样分子能够增强吞噬细胞的吞噬作用，但是,它不是单独起作用的，仍然必须依赖体腔液中其他未知成分，而对未知成分的鉴定需要进一步研究。

关键词：仿刺参吞噬细胞体腔液调理素样分子