过稳定化

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.

理论分析和试验研究表明： 1球轴承振动是钢球—滚道接触副中的各种摩擦学作用引起的，具有摩擦动力学的本质，任何对接触副的摩擦学特性有影响的因素都将对球轴承的振动和噪声特性产生影响； 2中心轴向载荷作用下，载荷增大使球轴承的固有振动频率升高，载荷越大同样的载荷增幅引起的频率升幅减小，足够大的中心轴向载荷作用下载荷的变化对球轴承振动的频率特性不会产生明显的影响； 3轴向和径向联合载荷作用下，径向载荷不大时球轴承振动的固有频率基本不变，但是可能引起变刚度激励的非线性振动，出现新的频峰，过大的径向载荷将使部分钢球脱离接触，使球轴承的振动和噪声呈现不稳定状态； 4润滑对球轴承的振动和噪声特性有重要的影响，良好的润滑对振动有明显的抑制作用，润滑不充分时，振动和噪声的水平会有明显增高，一定条件下还会激发接触副中的谐振，发出啸声，造成接触表面的伤害，无润滑干接触时，短时的运转就会损伤接触副表面，使振动和噪声迅速增大，并随时可能引发严重的磨损和卡滞失效；接触副润滑良好时，油膜的"刚化效应"使球轴承振动的固有频率有所提高，润滑剂中含有弥散性污浊时，振动的幅度总体升高，但弥散性污浊不会改变球轴承振动的频率特性；浙江大学博士学位论文：球轴承振动的研究 5低速时，球轴承振动的基本特征呈现不稳定状态，随着转速的提高，球轴承振动的频率特性趋于稳定，固有频率频峰升高； 6理论分析表明，干接触时钢球和滚道表面波纹度的某些谐波分量能激励球轴承的振动，振动的幅值与谐波幅值成正比，实际球轴承中钢球的分布不可能完全均匀，波纹度的激励作用会随时发生；润滑接触的分析表明，波纹度的任意谐波分量均能激励球轴承的振动； 7球轴承的几何和结构参数分析表明，球轴承尺寸越大，径向、轴向和角振动的固有频率越低；钢球中心圆直径增大，球轴承的径向和轴向振动的固有频率基本不变，角振动的固有频率有所上升，振动的幅频特性基本不变；径向游隙加大使球轴承的径向振动固有频率降低，轴向和角振动的固有频率有所升高，径向振动幅频特性的幅值升高，而轴向和角向降低；钢球的数量增多使球轴承振动的固有频率上升，幅频特性的幅值下降，径向振动的幅值下降最为明显；外圈沟曲率半径系数增大使球轴承径向振动的固有频率升高，轴向和角振动的固有频率降低，径向幅频特性基本不变，轴向和角向幅频特性幅值升高；内圈沟曲率半径系数增大使径向、轴向和角振动固有频率均下降，振动幅频特性的幅值均有升高； 8试验对比表明，传感器采用探针式安装时，由于探针接触副接触特性的影响，钡(量得到的球轴承振动信号有失真，采用专门设计和制作的试验球轴承，以固定式安装加速度计，首次测量得到了球轴承振动的真实信号，通过对振动信号的分析，验证了球轴承振动的理论模型； 9)基于时间序列分析的AR模型适用于大样本球轴承振动信号的分析，以样本长度的均方根值作定阶上界，FPE做判阶准则，给出的AR谱光滑，频率分辨率高，是球轴承振动分析的简便而可靠的手段； 10以时频域分析的小波包变换分析球轴承异音信号能够比较好地定位和聚焦异音发生的时间，时间间隔，频率范围，同样是球轴承振动分析的可靠的手段，可用作球轴承故障诊断技术。

This can be used to explain the changes of reverse transformation temperature AS of martensite in shape memory alloy. And thus, it is proved that the quenched-in vacancies are a main factor for stabilization of marten...

这一结果很好地解释了记忆合金马氏体逆转变温度As的变化规律，从而证明过饱和空位是Cu-Zn-Al形状记忆合金马氏体稳定化的一个主要原因。

Results are as followed:1 Exposure of HELF cells to BP caused c-Jun activation,and increased the activity of MAPK,PI-3K,p53 and cyclin D1 pathway.2 BP-induced c-Jun activation was inhibited by dominant negative mutants of extracellular signal-regulated protein kinase or c-Jun NH_2-terminal kinase,but not by p38,impling that JNK and ERK pathways medicate c-Jun activation induced by BP.3 Overexpression of dominant-negative mutants PI-3K and Akt potently blocked phosphorylations of c-Jun and ERK,but not JNK in response to BP,suggesting that PI-3K/Akt pathway positively regulates BP-induced c-Jun activation through ERK.4 Inhibition of p53 by its chemical or molecular inhibitor markedly increased the phosphorylation levels of c-Jun,Akt and ERK upon BP stimulation,indicating that p53 negatively medicates BP-induced c-Jun activation through PI-3K/Akt/ERK pathway.5 The cell lines expressed TAM67 exhibits no significant affecting normal cell growth properties.6 TAM67 was able to significantly block G_1-S transition and subsequent cell proliferation,suggesting that c-Jun is essential for cell cycle alternations elicited by BP.7 Overexpression of TAM67 impaired BP-induced cyclin D1 activation,decreasing expression of E2F1 and pRb,indicating that c-Jun participates in the modulation of BP-induced activation of cyclin D1/pRb/E2F1 pathway.8 Stably expression of TAM67 led to the increases in the expression levels of p53 and p21,elevating phosphorylation level of p53,clearly indicating that c-Jun regulates p53/p21 pathway activation induced by BRCollectively,PI3K/Akt/ERK pathway mediated BP-induced c-Jun activation through p53-dependent mechanism.

结果显示：1BP刺激细胞可促进c-Jun活化，并伴随着MAPK、PI-3K、p53和cyclinD1通路各组成成分的活性增强。2利用MAPK通路的显性失活突变体分别阻断细胞外信号调节激酶和c-Jun氨基末端激酶活性，均可明显抑制BP诱导的c-Jun活化，但阻断p38活性对BP引起的c-Jun活化无明显影响，提示JNK和ERK通路参与调控BP诱导的c-Jun活化。3过表达PI-3K和Akt的显性失活突变体也可显著抑制BP诱导的c-Jun活化，并降低磷酸化ERK的表达水平，但对磷酸化JNK的表达水平无明显影响，说明PI-3K/Akt通路通过ERK正性调控了BP诱导的c-Jun活化。4p53的化学/分子抑制剂能使BP作用的细胞内c-Jun活性明显增加，并同时诱导Akt和ERK的磷酸化水平的升高，表明p53可通过PI-3K/Akt/ERK通路对BP诱导的c-Jun活化进行负性调控。5随后观察转染细胞的生长情况，发现TAM67对细胞正常生长和形态无明显影响。6稳定表达TAM67可有效抑制BP诱导的S期细胞数的增加，提示c-Jun在BP致细胞周期改变的过程中发挥了重要作用。7TAM67过表达能够抑制BP诱导的cyclin D1活化，降低磷酸化Rb以及E2F1蛋白表达水平，表明c-Jun参与调控BP诱导的cyclin D1/Rb/E2F1通路的活化。8过表达TAM67可使BP刺激的细胞中p53、p21总蛋白以及p53磷酸化的表达水平明显升高，可见c-Jun也参与调控BP诱导的p53/p21通路活化。

The procedure of biscuit firing of clad plate base blank is carried out as follows: Weigh a certain amount of raw material in proportion by feeder, by conveyor belt the raw material is ground in a ball mill; after grinding for 12 hours, sifting-out and de-ironing, it is transferred to be homogenized and outworn in homogenization pool; then after spray drying granulation in spray tower, the powder is pressed into a certain size of blank by brick machine, afterwards, the blank will be dehydrated in drying kiln, through high-temperature sintering, base blank of clad plate with stable mechanical, chemical, physical performance has been finished.

复合板地柸素烧由以下环节组成：用喂料机按比例称取原料配料，通过传送带将原料传送到球磨机内球磨，球磨12小时后过筛、除铁，然后转移到均化浆池进行均化、陈腐、随后通过喷雾塔干燥造粒，将得到的粉料通过压砖机压制成所需规格的生柸，生柸在干燥窑干燥，随后在窑炉中高温烧制，得到具有稳定机械、物理化学性能的复合板底柸。

Lugalbanda was a god and shepherd king of Uruk where he was worshipped for over a thousand years.

Lugalbanda 是神和被崇拜了一千年多 Uruk古埃及喜克索王朝国王。

I am coming just now,' and went on perfuming himself with Hunut, then he came and sat.

我来只是现在，'歼灭战perfuming自己与胡努特，那麼，他来到和SAT 。