查询词典 pitch-black

It was a wonderful day, the applause at the Dall'Ara when I stepped onto the pitch, the fans gave me a great emotion with their chorus.

但今天很美好，当我踏上球场的草坪，球迷们给我的掌声和热情我都永远不会忘记。

Mourinho's is not the world's greatest tactician. Playing a holding midfielder in a 4-5-1 that turns into 4-3-3 in attack is not prophecy, it's a legacy of limited teams doing their damndest to compete with bigger, more skilled teams by defending all over the pitch and attacking in numbers.

穆里尼奥不是这世界上最完美的战术大师，在防守451、进攻433的体系里指派一个马克莱莱式的中场，这可不是"领先时代的战术"，而是古往今来人员有限的球队竭力与更强、更技术流球队交锋时的不二法门——全场防守，再伺机压上反击。

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。

Then Hideki Matsui, given the green light to swing at a 3-0 pitch, hit a liner to center. It would have been an out, but Darin Erstad broke in before going back on the ball, and it sailed over his head for a two-run double.

接下来上场的Matsui，在获得0好3坏球，可以尽管安心挥棒的情况下，打出一支中间方向的平飞球，本来应该被接杀的，但是白袜中外野手 Erstad冲太前面，来不及后退接球，结果球就从 Erstad的头上飞过去，造成两分得点的二垒安打。

So Darky rushed to the school alone. Lai Shun was not back yet, the school appeared pitch-dark. She became a little scared.

当下只身跑到学校去，来顺还没有回来，校内一片漆黑，她却有些害怕了。

Increase and decrease in volume or pitch, as if in waves

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Abstinence 6 hours of above. 1.2 spile method introduces recorder of the Digitrapper MDIII of Swedish CTD company, MDII PH, use vessel of small electrode of single crystal antimony, use standard amortize liquid first corrective PH value, the patient takes upright seat, cleanness is wet and rhinal, with lube before wet conduit paragraph, nasal cavity of a side of light firm will tracheal edge is inserted to pitch of head of patient of the enjoin when 15cm is controlled, make under the forehead stands by pectoral wall, in order to increase the radian of pharynx ministry passageway, make conduit is entered not easily by accident tracheal, and its do enjoin deglutition movement, slow guide conduit stomach, right now PH shows 1~2 is controlled, again will tracheal slow take out, when PH the value comes by .0 jump 5 when, judgement is ministry of gastric esophagus join , drag electrode 5cm to secure again with this.

禁食6小时以上。1.2插管方法采用瑞典CTD公司的Digitrapper MDIII、MDII型pH记录仪，应用单晶锑微电极导管，先用标准缓冲液校正pH值，患者取端坐位，清洁湿润鼻腔，用润滑油湿润导管前段，轻稳将导管沿一侧鼻腔插至15cm左右时嘱患者头部前倾，使之下额靠近胸壁，以加大咽部通道的弧度，使导管不易误入气管，并嘱其做吞咽动作，并缓慢将导管导入胃，此时pH显示1~2左右，再将导管缓慢抽出，当pH值由。0突升至5.0时，判定为胃食管连接部，以此将电极再拽5cm固定。

He thought I had abused his hospitality to make a demagogic pitch to white voters.

他觉得我滥用了他的盛情，对白人选民做煽动性的自我推销。

On the pitch, his demeanour is cold and clinical.

在球场上，他的行为冷静而实用。

Straightedge rule (square rule, slide gauge, inside and outsidemicrometer, steel tape, feeler, dial gauge, depth micrometer, wire gage,radius gage, thread pitch gage) is a kind of common measuring tool.

直尺（角尺、游标卡尺、内径和外径千分尺、钢卷尺、塞尺、千分表、深度千分尺、线规、半径规、螺距规）是一种常用量具。

She gently rebuff ed him, but agreed that they could be friends

她婉言拒绝了，但同意作为朋友相处。

If in the penal farm, you were sure to be criticized.

要是在劳改农场，你等着挨绳子吧！