The effect of tribology factors on bearing vibration is studied experimentally. AR model and WPT are used to processing the normal arid abnormal signals. The results are as follows:1. The vibration of ball bearings is caused by the tribology action of contact pairs of ball and ring races and has the essential of tribo-dynamics. Any factors affecting the tribology characteristics of contact pairs will affect vibration and noise of bearings consequently.2. Vibration characteristics of bearing keep almostly unchanged with the increasing of axial load expecting the increasing of nature frequencies. When radial load increasing with axial load unchanged, nature frequencies keep unchanged but some new vibration peaks appears in the spectrum.3. Vibration amplitudes are damped and nature frequency are enhanced with sufficient lubrication. Vibration and noise of bearings increase obviously and roar can happen and the contact surfaces scratch slightly under insufficient and unclean lubrication state. Bearing will be disabled in a few minutes without any lubrication.4. Bearing vibration is unstable under low speed. With the speed increasing, the vibration become stable and natural frequencies increase slightly but the amplitudes increase apparently.5. Bearing vibration can be excited only by some harmonics ofwaviness without lubrication and by all harmonics with lubrication based on the theoretical analysis.6. The nature frequencies of ball bearings decrease with the increasing sizes. When international clearance increasing, nature frequencies decrease in radial and increase in axial and angular and the amplitudes increase in radial and decrease in axial and angular. When the number of balls increasing, nature frequencies increase and amplitudes decrease. When the pitch diameter increasing, axial nature frequency increase and others nearly keep no change. When outer race groove curvature radius increasing, nature frequencies increase in radial and decrease in axial and angular and amplitudes keep no change in radial and increase in axial and angular. When inner race groove curvature radius increasing, nature frequencies decrease and amplitudes increase.7. The distortion in amplitude and frequency components of bearing vibration signals picked up by the present probe measurement method is founded and right conclusions cannot be achieved by the signals. When accelerometer is rigidly screwed with steel stud onto a flat outer surface of a ball bearing, vibration signal can be got without distortion and the reliability of research on bearing vibration is assured.8. AR model is suitable for large samples of bearing vibration signals, square root of length of samples can be used as the upper limitation of order determination and the FPE order selection criterion is effective. Many advantages of AR spectrum are founded over the classical based on FFT.9. Time-Frequency analysis is necessary for abnormal noise of ball bearings. WPT overcomes the principle shortcomings of STFT and proved to be a best tool to process the abnormal signals.

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The results show that, firstly, Stellera chamaejasme L, which rely on their developed axial root system in the 10～40cm soil layer to occupy the competitive priority of volume, length, surface area and so on, in the case of their adaptive faculty to poor surroundings resulting from fruit picking, trampling and overgrazing as well as with the phenomenon of restrained growth among various plants, gradually become the dominant plant in the herbaceous community; secondly, this kind of degraded grassland has not displayed any general characteristic of degradation such as surface exposure, accumulative quantity of vegetation reduced, water loss, soil erosion and so on, therefor, it should be dealt with distinguishingly; thirdly, if"Stellera chamaejasme L Killer"and"Oxytropis ochrocephala Killer"invented by CAS are taken advantage of respectively in the bloom period of Stellera chamaejasme L and at the beginning of florescence of Oxytropis ochrocephala bunge by ultra-low volume spray of 1. 05L/hm〓 and 1. 35～165L/hm〓 dosage separately, the death rates of poisonous herbs may achieve above 95% and 92% correspondently; fourthly, this technology with the characteristics of high work efficiency, exclusive selectivity and convenient operation, is safe to non-target plants and other animals, and has no toxic or side-effect to environment; furthermore, an execution of"Stellera chamaejasme L Killer"spray and a two-year grazing prohibition can be effectively applied on degraded grasslands of"Weed and Poisonous plants Type".

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At the same time, gene interaction was observed in some of characters, transgressive segregation gene interaction was observed in polygenes controlling length of axial root and thickness of root base （ 1cm）, complementary gene interaction was significantly detected in nodule number of lateral root and dry weight of lateral root and nodule number of lateral root, but not detected or significant in the others.

控制主根長性狀的多基因間存在互作偷窥偷拍视频，互作方式為重疊作用尤物视频网站免费；控制主根粗（3cm）性狀的基因間也存在一定的重疊作用，但是作用不明顯黄片香蕉；控制其他性狀的基因都存在互作色天天天综合色天天一区，表現(xiàn)為互補作用，但互補作用的強弱有差異91最新国产中文字幕。

axial root system：主根系

主根 axial root | 主根系 axial root system | 直根 taproot

taproot：直根

主根系 axial root system | 直根 taproot | 直根系 taproot system

taproot;axial root：軸根

軸根 taproot;axial root | 瀝青癌 tar cancer | 大風子樹(印度產(chǎn)) Taractogenos kurzii King