查询词典 spectrum analysis

In this work, the digital analysis of six Al-based standard alloy samples with different content of Mg has been performed. Using spectra of Mg 518.36 nm as the analysis spectrum line, Cu 510.55 nm and Fe 510.75 nm as comparison spectrum lines separately, quantitative analysis has been made.

对6种不同镁元素含量的铝合金标准样品进行了数字化分析测定，探索了选用Mg 518.36 nm作为分析谱线，分别选用Cu 510.55 nm和Fe 510.75 nm作为比较谱线进行定量测定的方法。

The digital analysis of the three standard samples of the Al-based alloy with different content of Cu, and the probe into the quantitative analysis that employs the spectrums of Cu 510.55 nm and Fe 510.75 nm as the analysis spectrum and comparison spectrum, indicate the positive relationship between the content of copper and the intensity ratio of the analysis and comparison of spectrum.

对3种不同Cu元素含量的铝合金标准样品进行数字化分析测定，探索选用Cu 510.55nm谱线和Fe 510.75nm谱线分别作为分析谱线和比较谱线进行定量测定的方法，数据显示分析谱线和比较谱线的强度比值与Cu元素含量呈正比关系。

The digital analysis of the six standard samples of the Al-based alloy with different content of Cd, and the probe into the quantitative analysis that employs the spectrums of Cd 508.5 nm as the analysis spectrum, Cu510. 55 nm and Fe510.75 nm as comparison spectrum separately, indicate the positive relationship between the content of cadmium and the intensity ratio of the analysis and comparison of spectrum.

对6种不同Cd元素含量的铝合金标准样品进行了数字化分析测定，探索了选用Cd 508.58nm谱线作为分析谱线，分别选用Cu510.55nm和Fe510.75nm谱线作为比较谱线进行定量测定的方法，数据显示分析谱线和比较谱线的强度比值与Cd元素含量成正比关系。

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。

A series of bulkily substituted ferrocenium triiodides with general formula (RC5H4)2FeI3 have been synthesized and characterized by elementary analysis, IR spectrum, mass spectrum, ESR spectrum, Mossbauer spectrum and conductivity.

通过元素分析，红外光谱，质谱，顺磁共振谱，穆斯堡尔谱和电导率对这些化合物进行了表征。

It is one of the most important method in chemical research. The course matches Instrument Analysis course. We set up 16 experiments: atomic absorption spectrum, atomic emission spectrum, atomic fluorescent, ultraviolet-visible absorption spectrum, infra-red absorption spectrum, and molecular fluorescent which are for photometric analysis; vottammetric analysis , coulometry analysis ,volt-ampere analysis and polarogarphy for electroanalytical chemistry; Gas chromatography and liquid chromatography for chromatographic analysis.

本实验内容与仪器分析理论课内容相配套，针对光化学分析开设了原子吸收光谱、原子发射光谱、原子荧光、紫外-可见吸收光谱、红外吸收光谱、分子荧光光谱等实验；针对电化学分析开设了电位分析法、库仑分析法、伏安和极谱分析法等实验；针对色谱分析开设了气相色谱和液相色谱分析等实验，共开设了16个实验。

However,the spectrum analysis method cannot reflect the evolution of the HF backscatter in time domain.

传统的谱分析方法，无法反映回波信号在时间上的演化规律。

Using modern spectrum analysis method and FFT, the specific value VLF/HF of Heart Rate Variabilityof 19 healthy individuals and 10 hyperthyroid is analysed .

利用现代谱分析法和FFT分析法，分析了19例正常人和10例甲亢患者心率变异信号的VLF/HF值。

By using modern spectrum analysis method, the specific values :VLF/HF of Heart Rate Variability of healthy persons and hyperthyroid s were analysed .

采用心电信号采集系统，将心电图机的模拟信号放大滤波后送入计算机，利用现代谱分析法分析了正常人和甲亢患者心率变异信号的VLF/HF值。

The possibility of surface contamination moving inside silastic is studied via energy spectrum analysis.

进而通过对高、低场强区材质的断面作扫描电镜，对比了材质在电老化、紫外老化因素下表现出的微观结构特征；通过对比伞裙侧表面和上下表面的微观结构，揭示了电老化和电烧蚀的发生规律；通过能谱分析，探索了表面积污向材质内部迁移的可能性。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。