变度

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。

Divergence variation of snow storm indicated that the formation of negative divergent variation in lower-layer predicted the shear convergence and the snow storm generation. Nongeostrophic vorticity and divergence of wind advection contributed to the divergence variation largely.

暴雪切变线的散度变率诊断表明，低层散度负变率带及中心的生成和发展预示着未来时期内切变线辐合区的形成和发展及暴雪天气的发生，其中非地转涡度和风速平流的散度项对散度变率的贡献较大。

Created a piezo element with the world's highest degree of distortion through film thickness reduction and materials development.

通过减小压电薄膜的厚度，开发出了世界最高的曲变度的压电薄膜元件。

In metastable equilibrium phase diagram of quinary system Li+, Na+, KV/C032, B4O72 -H2O at 288K, there are six crystallization fields (saturated with Li2CO3): K2CO3 -3/2H2O, Na2CO3 MOHjO, NaKCO3 -6H2O, K2B4O7 5H2O, Li,B2O4 -16H2O and Na2

五元体系Li~+，Na~+，K~+∥CO_3~(2-)，B_4O_7~(2-)—H_2O 288K稳定相图中，有六个Li_2CO_3饱和的结晶区：K_2CO_3·3／2H_2O，K_2B_4O_7、·4H_2O，Na_2CO_3·10H_2O，Na_2B_4O_7·10H_2O，NaKCO_3·6H_2O及Li_2B_4O_7·3H_2O；九条单变度曲线及四个无变度点。

Study on knojac coating storing of taro without skin;2. Different package treatments on fresh-cut taro Colocasia esculena

与对照、聚乙烯塑料薄膜包装相比，4℃贮藏的前12天，真空包装能较好地保持鲜切芋头的可溶性固形物含量和淀粉含量，褐变度、丙二醛含量和多酚氧化酶的活性较低，而超氧化物歧化酶活性较高。

Product fault ink UN-uniform UN-uniform ink products were:(1) water and ink, ink and wash painting the rubber roll version of wear, spindle bearing wear, cots epiderm aging decline, ink, etc;(2) series water roll of layer debranning, cylindricity wear, a thin layer of shoulderpieces for intergradle monlchamus, a product of long a portion of the Ribbon, resulting in a roller 跞 movement oscillating anisotropism;(3) support by Edition of water, rollers, the cylinder, swayig stand, wear, resulting in version tiaodong Cot by cause pressure by version is unstable, produce ink imbalance, ink, ink plate, staves, relying on the old version (students'overloaded) version of COTS and pressure;(4) the water roll chemiluminscent set of aging or poor quality water decline caused by transmission;(5) does not have a regular check of the drum-and-ink roller and version by version-and-ink roller and pressures;(6) if the drum gear wear, and gear spacing is the same as the regular ink "" gear.

二、产物墨色不平均障碍产物墨色不平均的来因有：（1）传水、传墨、匀墨和靠版水墨各橡胶辊的圆柱度磨损超不差，拆轴承的轴脚磨损，胶辊不内脏嫩化，传墨本领回升等；（2）串水辊度层脱皮，圆柱度磨损超不差，暗地有薄积墨层，两脚长出局部有积墨带，变不败滚子跞不静串墨不不平衡；（3）撑持靠版水、墨辊的锁脚，摆不静支架，磨损惨重，变不败胶辊靠版时跳不静致使靠版不抬辛不安定，爆发水墨不不平衡，呈现墨色不不平衡、干版、水墨杠、嫩版等本体；（4）水辊绒套嫩化或质度不差变不败传水本领回升；（5）操纵按期校核各水墨辊及版滚筒与靠版水墨辊的不抬辛；（6）若滚筒传不静齿轮磨损超不差，呈现与齿轮间距不异的有次序的&齿轮墨杠&。不一、套印障碍 1。

Based on the study on the monovariant eutectic reaction in Al-Mg〓Si-Mg〓Ge ternary system, possibility of using the composite compound as the strengthening phase was examined primarily.

通过对Al-Mg〓Si-Mg〓Ge系中单变度共晶反应的研究，对复合型化合物作强化相的可行性作了初步探讨。

Three types of base asphalt and six SBS were used to produce SBS modified asphalt. The interaction of SBS modified asphalt was discussed in different states between the base asphalt and SBS based on their compositions. Through the traditional tests, such as penetration, soften point and ductility, and US SHRP tests, the results indicated that influences to affect the temperature susceptibility, high and low temperature performance, aging characteristics are base asphalt, SBS types and their dosages. The functions of penetration to viscosity and complex shear modulus G~* to complex dynamic shear viscosity η~* were set up, and then theviscosity-temperature susceptibility of wide temperature span and the calculation method of low temperature viscosity were obtained."Process" evaluation criterions, high grading critical temperature T_ and low grading criticaltemperature T_ , were suggested according to the high and low temperatureperformances of SBS modified asphalt. Using the experience of Repeated Creep and Recovery Test for Binders, a new high-temperature evaluation index,modification rutting factor G~*~(-9) was obtained. The results after RTFO and PAV aging indicated that traditional tests didnt differentiate base asphalt and SBS modified asphalt, but dynamic mechanics temperature spectrum and G*-5 black chart clearly reflected the influence of aging to the SBS modified asphalt. With the IR and GPC tests, the reason of aging to the SBS modified asphalt were due to asphalt phase oxygenated and SBS phase depredated.

论文选择3种油源的基质沥青和6种SBS改性剂制备改性沥青，通过分析基质沥青和SBS改性剂的组成结构特点，得出了不同状态下SBS改性沥青的SBS与基质沥青的相互作用机理；通过针入度、软化点、延度等常规试验以及美国SHRP试验，分析了基质沥青、SBS改性剂类型与剂量对SBS改性沥青的温度敏感性、高低温特性及老化特性的影响；建立了针入度-粘度、复数模量G~*-复数粘度η~*的换算关系，得出了宽温度域的粘温指数VTS和较低温度下粘度的计算方法；通过高低温性能分析提出了&过程&评价参数高温等级温度T_和低温等级温度T_；借鉴重复恢复与蠕变试验研究成果，得到了SBS改性沥青高温评价指标改进型抗车辙因子G~*~(-9)；RTFO和PAV老化后的性能试验结果表明，常规试验难以区分SBS改性沥青与基质沥青的差异，而动态力学温度谱、G~*-δ黑斑图可以反映老化作用对SBS改性沥青的影响，且通过IR试验和GPC试验得出SBS改性沥青老化是沥青相的氧化和SBS的降解共同引起的；通过不同温度下SBS改性沥青混合料的旋转压实SGC试验，根据粘度与剪变率的关系，提出用剪变率60(1／s)测试SBS改性沥青的粘温曲线，并按照0.17±0.02Pa.s和0.28±0.03Pa.s确定施工温度。

In view of the total analyze table, and then change the formula for the number of a composition or formula of a variable results immediately, color, regain color, back color, or leave the despensing Center.

在总阐发外洋查察配方，然后保持配方洋某个身不合的数度或配方的某个变度便可当即得知甘休，务必从头测色，从头取回颜色，从头配色或挨近配方边缘。

However, in large differential pressure operating conditions, evaporation pressure has eased, the evaporator load requirements of the fluid volume decreased, but the actual situation the contrary, in the suction superheat unchanged, due to evaporation pressure has eased, the evaporator outlet pressure be reduced accordingly, pressure changes above and below the diaphragm, causing the main valve opening increases for increased fluid; but in a small pressure operating conditions, evaporation pressure rise, evaporator load demand for fluid volume increased, but the reality is that in the suction gas superheat unchanged, due to evaporation pressure rise, a corresponding increase in the evaporator outlet pressure, pressure difference above and below the diaphragm smaller, so that the main valve opening decreased for the reduction of liquid volume; in variable load is all about.

但在大压差工况下，蒸发压力降低，蒸发器负荷需求的液量减少，但实际情况相反，在吸气过热度不变的情况下，由于蒸发压力降低，蒸发器出口压力相应降低，膜片上下的压差变大，使主阀开度增大，供液量增加；但在小压差工况下，蒸发压力上升，蒸发器负荷需求的液量增多，但实际情况是在吸气过热度不变的情况下，由于蒸发压力上升，蒸发器出口压力相应提高，膜片上下的压差变小，使主阀开度减小，供液量减少；在变负荷下亦如此。因此热力膨胀阀在变工况下供液量的调节方面需进一步改进。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。