可增大的

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 results indicate that the flow stress of the alloy increases with increasing strain rate and decreasing deformation temperature. The flow stress increases with increasing strain until the stress reaches the peak value, then the flow stress remains constant, which indicates that dynamic recrystallization happens during deformation. The flow behaviors are described by the hyperbolic sine constitutive equation, and the activation energy calculated is 337.75 kJ/mol. The as-forged microstructure consists of refined α2/γ and γ grains, and the grains are much homogeneous than before. The B2 phase distributes uniformly at the grain boundary of α2/γ and γ grains. The B2 phase decreases with increasing deformation temperature.

结果表明：流变应力随着应变速率提高和变形温度降低而增大；在变形过程中，流变应力随着变形量增大而增大，当流变应力达到峰值后趋于平稳，表明合金在变形过程中发生了动态再结晶；热变形过程的流变应力可采用双曲正弦本构关系来描述，平均激活能为337.75 kJ/mol；从合金的组织演化过程中可以看出，合金中不均匀的原始组织得到明显均匀化，变形后的组织是由α2/γ层片晶团和γ晶粒组成的双态组织，在α2/γ层片晶团和γ晶粒的晶界交界处发现分布均匀的B2相，并且随着变形温度升高B2相数量逐渐减少。

And there is an approximate linear relationship between the momentum of the automatic mechanism and the length of the gas tube.

如β=〓与β=〓相比较（β角单位为弧度，其定义详见正文），前者与后者对应的气室最大压力之比可达65%，而对应的自动机动能之比可达60%；导气管内径对气室内气体压力冲量和自动机动能的影响存在极值点，且该极值点随导气孔的增大而有规律的增大；导气管长度对气室最大压力、压力冲量和自动机动能的影响呈单调递减规律，且自动机动量与管道长度之间近似符合一直线关系。

The results show that the amorphous PLGA fiber with porous structure (0.1-1.0 μm) is obtained by diluted solvent spinning method and the mechanical properties is affected by pressure and temperature. Bending strength and shearing strength of the samples increase firstly and then decrease with the increase of molding temperature and pressure. While the molding temperature is 160℃and the pressure is 105MPa, the PLGA materials possess optimal mechanical properties, bending strength, shearing strength and bending modulus 187.3 MPa, 100.0 MPa and 2.5 GPa, respectively. The mild temperature molding PLGA materials are desired to play a grate role in non-bearing internal fixation devices.

研究结果表明：非晶多孔结构的PLGA纤维可通过溶液沉析纺丝的方法获得，其孔径为0.1~1.0μm；压制压力和压制温度对材料的力学性能影响较大，材料的抗弯强度、剪切强度和抗弯模量均随着温度和压力的增大而先增大后降低；在压制压力为105MPa，压制温度为160℃时，试样的力学性能比较理想，此时，其抗弯强度可达到187.3MPa，剪切强度达到100.1MPa，抗弯模量达到2.5GPa，可望作为非承重部位骨折愈合内固定材料。

The main characteristics include: the quiet Sun corona has a rapid response to the flare heating, within 2 second the corona temperature increases nearly one order of magnitude, but later such increase becomes very slowly; the downward velocity at early stage of impulsive phase is too small to be negnected; chromospheric evaporation made by conduction shows some intensely, the maximum evaporated velocity may be as large as 1000 km/s; the chromospheric condensation appears just when the chromospheric evaporation takes place and its place always coincide with that of transition region in the early stage; the maximum of chromospheric condensation occurs also in the early stage of impulsive phase, at which the density in condensation may be larger two order of magnitude than that of surround and the downward velocity may be as large as 100 km/s; after the maximum of chromospheric condensation, its strongth decreases gradually but its width becomes greater with time and have a tendency to transport into deep chromosphere; the front of chromospheric condensation heats atmosphere obviously and the temperature in the chromospheric condensation is higher than the original case; the downware velocity of transition region may be greater than 100 km/s at the early stage; when the evaporated material collide at the top of loop, the densityand the presure there increase rapidly, which result in the formation of a shock wave; and so on.

在改善色球辐射损失和精确分辨过渡区的基础上，通过联立求解连续性方程、动量方程和能量方程，构造了一维磁限制性耀斑环在热沉积作用下的大气动力学模型，获得了耀斑热模型下脉冲相早期较为细致的大气演化理论图象，其主要特征是：耀斑对宁静日冕的加热相当迅速，仅2秒钟日冕温度增加即达一个量级，之后日冕温度增加缓慢；脉冲相早期日冕向下速度很小，几乎可以忽略，热传导驱动色球蒸发，其过程较为激烈，蒸发极大速度可达到1000km/s；色球压缩区与色球蒸发几乎同时形成，且在早期其位置总是与过渡区位置重合；色球压缩极大发生在脉冲相早期，其时密度可高于周围约2个量级，向下速度可超过100km/s；色球压缩极大后，其强度逐渐减弱，但宽度明显增大，且渐渐脱离过渡区往色球传播；压缩区内物质温度要高于原先的大气温度；过渡区下降在脉冲相早期相当迅速，可超过100km/s；当蒸发物质在环顶高速相碰时，环顶的密度、压力迅速增大，且温度也有所增加，导致形成激波，其波面以每秒上百公里的速度自环顶向下传播；在脉冲相前期，日冕软x辐射对色球的加热作用可以忽略；等。

Theoretical analyses indicate that the reduction of internal relative humidity or so_called self_desiccation of HPC may be mainly caused by the increase in the mole concentration of soluble ions in HPC and the fractions of gel water, absorbed water and interlayer water in the total amount of evaporable water.

理论分析表明，混凝土中可溶离子浓度的增大，及凝胶孔水、吸附水、层间水在总可蒸发水量中的比例增大是导致HPC自收缩或自干燥的主要机理。

The suspicion of cancer is increased by the following factors:(1) age (young patients are more susceptible);(2) sex, if the patient is a man (more women have thyroid cancer by a ratio of 2:1, but women have more thyroid disease by a ratio of about 8:1; thus, a man with a nodule should be regarded with greater suspicion);(3) a solitary nodule (multinodular lesions are usually benign unless there is a dominant cold nodule by thyroid scan);(4) a cold nodule on thyroid isotopic scanning (hot nodules are seldom cancerous);(5) a history of radiation exposure to the head, neck, or chest, especially in infancy and childhood (eg, for an enlarged thymus or enlarged tonsils, acne, or lymphoma);(6) radiographic evidence of fine, stippled psammomatous calcification or dense, homogeneous calcification;(7) recent or rapid enlargement; and (8) stony-hard consistency.

下列因素可增加癌的可疑性：(1)年龄；(2)性别，如果病人为男性(女性与男性的甲状腺癌比为2：1，但女性更多的是得甲状腺病，约为8：1，因此，男性有甲状腺结节时应考虑癌的可能性更大)；(3)孤立小结(多结节病变一般为良性，除非甲状腺扫描时呈明显的冷结节)；(4)甲状腺同位素扫描时发现冷结节；(5)有过头、颈、胸放射接触史，尤其是婴儿和儿童期(例如，因胸腺增大或扁桃体肿大、痤疮或淋巴瘤等)；(6)X线片见细、斑点状、沙粒样钙化或致密、匀质钙化；(7)最近增大或快速增大；(8)质地石头样坚硬。

Two different velocity potential functions corresponding respectively to the liquid above and below the damping spacer are assumed.

研究表明：在相同密度分布条件下，可压缩流体的界面扰动增长速率总是比相应的不可压缩流体的界面增长率大，其相对增长率D随扰动波长的增加而增大，也随两种介质的声速减少而增大，在长波和易压缩流体中，D值可达0.8以上。

The experimental results show as follows: Slag could inhibit the cracking of concrete within the range of certain proportion. With the increase of slag proportion the self-shrinking of concrete increases, but the drying shrinkage of concrete decreases.

结果表明矿渣掺量在一定范围内时可抑制混凝土的开裂，混凝土的自收缩随矿渣掺量的增大而增大，干缩随矿渣掺量的增大而减小。

The experimental results show as follows: Slag could inhibit the cracking of concrete within the range of certain proportion. With the increase of slag proportion the selfshrinking of concrete increases, but the drying shrinkage of concrete decreases.

结果表明矿渣掺量在一定范围内时可抑制混凝土的开裂，混凝土的自收缩随矿渣掺量的增大而增大，干缩随矿渣掺量的增大而减小。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。