不大可能

Although hasten of near future of upriver cooking benzene is firm, but the range that the market rises is not big, each manufacturer is maintained more move smoothly, the amplitude modulation on shipment price is lesser, to suitable anhydride market prop up gradually firm, if crude benzole market goes high further, driving the possibility that cooking benzene rises is not to do not have, the crude benzole stock of manufacturer of each cooking benzene and benzene hydrogenation manufacturer is not at present much, the crop of cooking benzene is not big, market supply of goods is not much, do not eliminate small to walk along high probability.

虽然上游焦化苯近期趋稳，但市场上涨的幅度不大，各厂家多维持平稳运行，出货价格上调幅度较小，对偏苯三酸酐市场的支撑渐稳，若粗苯市场进一步走高，推动焦化苯上涨的可能性不是没有，目前各焦化苯厂家和苯加氢厂家的粗苯库存并不多，焦化苯的产量不大，市场货源不多，不排除小幅走高的可能。

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。

The wage rate structure, in fact, may become even more distorted; for the great mass of unorganized workers, whose wage rates even before the inflation were not out of line (and may even have been unduly depressed through union exclusionism), will be penalized further during the transition by the rise in prices.

事实上，工资率的结构甚至可能变得更不公平——众多没有参加工会的工人，他们的工资水平甚至在通货膨胀之前就不大符合他们应得的标准（甚至可能因为遭受工会排挤，而被压得过低），而在物价上涨的过渡期间，他们的处境将进一步恶化。

The wage rate structure, in fact, may become even more distorted; for the great mass of unorganized workers, whose wage rates even before the inflation were not out of line (and may even have been unduly depressed through union exclusionism), will be penalized further duringthe transition by the rise in prices.

事实上，工资率的结构甚至可能变得更不公平——众多没有参加工会的工人，他们的工资水平甚至在通货膨胀之前就不大符合他们应得的标准（甚至可能因为遭受工会排挤，而被压得过低），而在物价上涨的过渡期间，他们的处境将进一步恶化。

It was found greater expression of NRP2-1 and NRP2-2 in pituitary, ovary, uterus and oviduct of ruttish Erhualian than corresponding tissues of ruttish Duroc, which suggested enhancing expression of NRP2 was favorable to increasing litter size. But the difference of NRP2 expression was not significant between two breeds, which suggested the key phase that NRP2 affected litter size was not oestrum probably, or NRP2 could enlarge cell signals and finally affect litter size ascribe that it was the receptor of nerve axon guidance factors.

NRP2-1和NRP2-2在发情期二花脸卵巢、子宫、输卵管中的表达量均大于杜洛克相应组织的表达量，推测NRP2表达水平高可能有利于提高产仔数，但两品种间表达差异不明显，推测NRP2影响产仔数的关键阶段可能不是猪的发情期；另外，NRP2 是神经轴突介导因子的受体，这些神经轴突转导的信号往往有级联放大的功能，虽然NRP2-1和NRP2-2在二花脸和杜洛克卵巢、子宫、输卵管中的表达差异不大，但二花脸有可能通过神经系统转导信号的级联放大最终引起一些效应激素或蛋白的急剧增加，从而提高排卵率或产仔数。

When food and water were abundant, the density dependent social factor did not affect the reproductivity, which implied that food instead of social factor might be the key factor in determining the change of reproductivity of the hamster in field.

在食物和水分充分供应的情况下，围栏内种群密度的高低对雌鼠繁殖力的影响不大，说明食物可能是引起野外大仓鼠种群繁殖力变化的关键因素，而社群因素的作用不大。

According to Dr. Abramov, possible explanations for the lack of benefit include the limited pain intensity with transvaginal pelvic surgery; the short duration of preemptive analgesia (no boluses were given postoperatively); and the chance that the effect was masked by patient-controlled analgesia overdose, which he said was unlikely.

根据Abramov博士的说法，在阴道骨盆重建手术时，先进行会阴神经阻断麻醉，对於疼痛强度方面的助益不大，可能归因於阴道骨盆手术所产生的疼痛是有限的，预先麻醉期间较短；至於其效果可能被过量之管制性麻醉药给掩盖过的说法，Abramov博士表示不太可能。

But that's not an argument likely to win favor among many people in the Deep South of the United States.

但这种说法看来不大可能赢得美国南方腹地几个州的人民的响应。

That's scarcely likely though; for whatever secrets Lieutenant Maldon may have, it's not very probable that this woman has any knowledge of them.

可看来又不大象；因为，不论马尔东上尉有什么秘密，这个女人是不大可能知道其中任何情况的。

In so far as it reflects a tough stance on immigration, the crisis on Lampedusa is unlikely to erode support for the government.

政府在对待移民问题上立场强硬，而兰佩杜萨岛上的危机不大可能会侵蚀民众对政府的支持。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。