axial root

axial root的基本解释

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主根, 直根, 轴根

与axial root相关的网络例句 [注：此内容来源于网络，仅供参考]

Root-derived organic carbon is composed of three compartments: root detritus, root eaudates and root symbionts, which represents a large important and potential C sink in forest ecosystems, The known responses of root derived organic carbon and heterotrophic microbes to elevated CO2 were reviewed. Overall, increases in root biomass, productivity, and exudation indicate an augmentation of C inputs into the soil via roots, although changes in root lifespan are still unclear and may modify this flux positively or negatively, Altogether, changes in root chemistry and morphology that may augment soil C storage under elevated CO2 include decreased N concentration and wider root diameter, Alternately, a shift in rooting depth upwards in the soil profile may increase average turnover rates of root detritus. Effects of CO2 concentration on C qualities of root exudates and root symbionts are the least understood components discussed here, Changes of soil heterotropic microbial activity and community under elevated CO2 still remained large uncertainties.

林木根源有机C包括根东通过根枯落物、根系分泌物和根共生菌周转3条途径向土壤输入的有机C，它是森林生态系统中一个重要的、潜在的C汇，综述了根源有机C与其微生物对CO2浓度升高的响应，虽然对根系寿命的变化尚不清楚，但CO2浓度升高将导致根系生物量、生产量、死亡量和分泌物的增加；同时，CO2升高亦促使根共生菌生物量的增加而增加了共生菌的C归还潜力，表明CO2升高使根源有机C的输入增加了，CO2农度升高情况下，根系化学性质和形态特征的这些变化均有利于增加土壤C的吸存；而根分布深度的降低则对土壤C吸存不利；CO2浓度升高对根分泌物和根共生菌质量的影响研究则极少，CO2浓度升高下土壤微生物活性和群落组成的变化存在较大的不确定性，目前CO2浓度升高下林木根源有机C对森林长期C吸存的贡献仍很不清楚。

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。

Hairy roots were induced from tobacco leaves with Agrobacterium rhizogenes LBA1334 harboring agropin type PRil855 and binary vector PIG121HM carrying a kanamycin resistant gene nptll and GUS gene and the good hairy root clones were selected. The root with many root hairs and branches grew vigorously toward all the direction on MS medium without plant hormone and on kanamyain containing medium (km:30mg/L). The structure of the hairy root tip is different from that of ordinary root. Witch was not typical root cap maybe the main cause of losing the geotropism of hairy root. Plantlet regenerated from hairy root when cultured on Ms medium without plant hormone. The nicotine content of the hairy root was little higher than that in the natural roots.

本研究通过发根农杆菌工程菌LBA1334(含有野生型pRi1855质粒和pIG121HM双元载体质粒，编码NPTⅡ基因和GUS基因)转化烟草沙姆逊，获得了具有卡那霉素抗性烟草发状根，并筛选出良好的单克隆株系，该发状根具有典型的发状根特性(多根毛、多分支、在无激素培养基上快速生长)，通过根尖压片分析，烟草发状根不具备典型的根冠；发状根中烟碱含量1.61％稍高于与天然栽培品种母体根的含量(1.5％左右)，发状根向培养液中释放烟碱，释放量最多时占总烟碱量的81.1％；在无激素的培养基上获得了再生植株。

与axial root相关的网络解释 [注：此内容来源于网络，仅供参考]

root apex;root tip：根端

根苗复合体 root and shoot complex | 根端 root apex;root tip | 根端 root apice;root apex; root tip

axial root system：主根系

主根 axial root | 主根系 axial root system | 直根 taproot

axial field：轴向场

axial 轴向的,沿轴的 | axial field 轴向场 | axial search coil 轴向探察线图