查询词典 axial shoot

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。

We proposed a set of tabulate shim coils to improve the imaging field homogeneity for permanent magnet. By studying the magnetic spherical harmonics and its Taylor expansion, the proposal of designing lower-order radial coils was derived including x, y, xz, xz~2, x~2-y~2 etc. In addition, a novel composite design was presented for the axial coils. By controlling the shim currents of axial coils, different axial magnetic fields can be obtained. This method simplified the design process of axial coils, and made the axial correcting magnetic field more precise.

本文针对永磁体的组成结构提出了一种平板式匀场线圈设计方法，通过研究成像磁场的球谐函数以及通电圆弧在自由空间产生磁场的泰勒展开级数，导出了x、y、xz、xz~2、x~2-y~2等低阶径向线圈的设计方法，同时针对轴向线圈提出了一种新的混合式设计方案，能够通过控制线圈中的电流组合实现对不同轴向磁场分量的获取，简化了轴向线圈的设计过程，提高了校正磁场的准确性。

In general, the design work with traditional measures is done by hand, which cannot meet the needs of the technology and manufacture. So the author has developed a CAD hydraulic design software fit for lower specific speed axial flow runner, which is easily operated by users.The main research work of this paper is as follows:1 Analyzing the main reason of axial flow power station cannot work well under littler volume of flow in some season and putting forward an improving scheme, pointing out the characters of design under abnormal factors.2 Combined with the development of the industry in our country, the abnormal hydraulic design method of propeller turbine is discussed based on present literature, data and experiment results.3 Guided by the design method of software engineering, a suit of hydraulic design software of Lower Specific Speed Axial Flow Runner is programmed by the object-oriented programming language Visual Basic and a straightforward, concise and standard Windows human-computer dialogue interface is designed for the system, which makes the operation of the system very convenient.4 ActiveX Automation technology is adopted as the interface with AutoCAD and the hydraulic drawings are edited, modified by AutoCAD until hydraulic model drawings according with the demand of engineering practice are output.5 To resolve practice problem, the author has designed a lower specific speed axial flow runner for Duowa Power Station through an example.

论文的主要内容有：1 深入分析很多轴流定桨式水电站枯水季节小流量下不能发电的主要原因，提出减容改造方案，并指出超常规条件下的改造设计特点。2 结合国情及行业发展需要，参考现有资料、文献和前人的研究成果，进行低比转速轴流式转轮叶片水力设计方法的研究，对轴流式转轮叶片的奇点分布法水力设计进行了全面的探索，结合现代计算机技术，找到了一种针对特殊条件的轴流式转轮叶片水力设计方法。3 仔细比较多种AutoCAD二次开发工具后，结合本课题的特点，选用Visual Basic语言，综合应用软件工程的设计思想，进行低比转速轴流式转轮叶片水力设计软件的编制，为系统设计了直观、简洁和标准的Windows人机对话界面，便于用户操作；编程时在考虑到设计条件特殊性的同时，尽量做到程序的通用性，使之可用于解决同一类问题；另外，大部分程序还可移植到普通轴流式转轮叶片水力设计中，具有良好的适应性。4 利用ActiveX Automation技术与AutoCAD接口，对AutoCAD进行二次开发，在AutoCAD下实现水力图的自动生成和编辑，直至输出符合实际工程要求的木模图。5 通过算例，为多哇水电站设计了一个低比转速轴流定桨式转轮，解决其在枯水期小流量下不能发电的问题。

A washer has a body having an axis and provided with a first bearing face surface located at one axial side and adapted to cooperate with a nut, a second bearing face surface located at an opposite axial side and adapted to cooperate with an object, at least one third turning resistant surface adapted to cooperate with a thread of the bolt, the body having at least one resistive point arranged so that when the nut is turned and turns the bolt the body of the washer stops the bolt from turning and thereby the nut creates a pull on the bolt which elongates the bolt in an axial direction and applies to the body of the washer an axial force which overcomes the at least one resistive point so that a portion of the body of the washer is allowed to be pulled axially when the bolt elongates.

一种放在螺帽与物体之间的垫圈，螺帽与螺栓螺纹连接，螺栓插入在包括两个装配的部件的物体内，垫圈具有主体，和设有第一支承面表面，位于一个轴向侧面和与螺帽配合，第二支承面表面，位于相对的轴向侧面和与物体配合，以及至少一个第三转动阻力表面，与螺栓的螺纹配合，从而使螺帽以给定的扭矩在一个方向转动同时垫圈的主体沿相对方向接收给定的力时，仅有螺帽转动，以紧固或松开螺栓，而垫圈的主体和螺栓保持静止。

The turbine comprises at least one radial or diagonal turbine stage (120) with radial or diagonal feed stream and axial exhaust flow and at least one axial turbine stage (121 - 125) with a axial feed steam and axial exhaust flow.

该涡轮机包括至少一个带有径向的或者对角线的入口和轴向的出口的径向的或者对角线的涡轮机级(120)和至少一个带有轴向的入口和轴向的出口的轴向涡轮机级(121-125)。

Based on theory and test, finally, the measurements which may reduce axial force are given, for example, strengthening the management of size and clearances in roll systems and maintenance of roll bearings, limiting rolling technological conditions, increasing the axial flexibility, releasing axial binding forces and establishing axial flexible lock mechanisms, etc.. So it provides the constructive suggestions for preventing from damage of roll bearings.

在理论分析和实验验证的基础上，分析了轧辊轴承的受力特点和破坏原因，提出了降低轴向力的对策，其中包括加强尺寸及间隙管理、限定工艺条件、加强轴承的维修与管理等&硬&性措施，以及增加辊系轴向柔度、施放约束、建立柔性锁紧机构等&软&性措施，为现场解决轴承损坏问题提供了建设性参考意见。

The morphological and anatomical characteristics of"Zha′ai 76"Comparing with the plants of normal M.baccata and ordinary hybrid,"Zha′ai76"and other plants with Dw major gene showed that:the length of springgrowth or main shoot is shorter by 59.6-66.2%;the ratio of length:diame-ter of new shoot smaller by 33.2-58.4%;the length of internee shorter by14.0-42.7%:the node number of spring growth lesser by 40.7%;the cauli-cle height under the cotyledons of hybrid seedlings shorter by 65.0%;the in-dex of leaf stalk(stipe length:stipe thiek ness)on the spring growth smaller by34.5-50.2%;the length of leaf stalk shorter by 25.2-45.7%;the boundarybelt between spring and autumn growth has knob-like nodes;the margin of leafappears wave-like;the sepals with spinous proeessuses are massive and small;the eonstriction at calyx is not obvious;the trace of abscisic sepals is big;the ca-lyx end of fruit is plan or convex;the shape of shoot tip(of"Zha′ai 76")iswider and shorter;and in 1.0mm part from the top of shoot tip,there are manyspecialized cells which are larger in volarae,but with lesser inner material andwith smaller or no nucleus.

"扎矮76"的形态解剖特征与普通山定子和杂交后代中普通型植株对比，"扎矮76"和其它携带Dw主基因植株的：春梢短59.6-66.2％，梢长与梢粗比值小33.2-58.4％，节间短14.0-42.7％，春梢节数少40.7％，杂种苗下胚轴短65.0％，春梢叶柄形指数小34.5-50.2％，叶柄短25.2-45.7％，春秋梢交界处有瘤状突起，叶缘波状，萼片肥厚有刺状突起，萼部缢痕不明显，脱萼后萼痕较大、萼洼平或高于果面；新梢生长点宽而短，在距顶端1.0gmm处有较多体积较大、内容物较少、细胞核小或无的待化细胞。

And then adding NAA at low concentration in MS was used to give rise to roots. We also found that lower level of hormone could control effectively browninng and vitrifaction during the culture and G1 n (6mg/L) and AgNOj (2mg/L) supplemented in shoot induction media could improve the shoot information rates apparently (about90%).The whole period of plant regeneration from leaflets of peanut could be divided as five steps: germination - shoot induction -shoot elongation-rooting- tranplant.

用1／2MS培养基萌发花生种子，9-10d后，从无菌花生苗上切取幼嫩叶片中部为外植体。2500Lux光照和27±1℃条件下，在诱芽培养基(MS+BA3mg／L+NAA0.8mg／L+AgNO_32mg／L十Gln 6mg／L)培养12-14d即可观察到明显芽点或瘤状突起，较前人报道的培养时间大大缩短了，4w后芽点进一步发育成丛生芽，芽诱导率达90.2％，每个外植体平均产9个丛尘芽，然后转至培养基MS+BA3 mg／L+AgNO_32 mg／L上诱导芽的伸长，3-4w后可长至3-4cm，切下带有2-3片叶片的幼芽移至生根培养基(MS+NAA0.8mg／L+AgNO_32mg／L)，1w后切口处可见白色不定根形成。

Quercetin, quercetin rhamnoside, hyperin, syringoside and eleutheroside E wereisolated from the flower of Acanthopanax senticosus. Searching bioactive natural compound and establishing quality evaluation standard arefocused on this experiment. Using cold immersing of 70% methanol to extract from flower ofAcanthopanax senticosus and integrating macroporous resin, silica gel column chromatography,sephadex gel to abstract. We obtained five monomer compounds (compoundⅠ-compoundⅤ),quercetin, quercetin rhamnoside, hyperin, syringoside and eleutheroside E. That five compoundswere determined by HPLC in eight parts of Acanthopanax senticosus (flower, root, leaf fruit,shoot, new shoot, phloem of shoot, skin of shoot), which provide science bases for establishingquality evaluation system and settle infarctate foundation.

本文以从刺五加花蕾中寻找具有重要生物活性的天然化合物和建立质量评价标准为主要目的，对其化学成分进行研究，采用70％甲醇冷浸的方法对刺五加花蕾中的成分进行提取，运用大孔树脂吸附色谱法、硅胶柱层析法以及葡聚糖凝胶柱层析相结合的方法进行分离，得到5种单体化合物，分别为槲皮素、槲皮素鼠李糖苷、金丝桃苷、紫丁香苷和刺五加苷E；利用高效液相色谱法对这5种化合物在刺五加花蕾中的含量进行了测定；考察了8个部位(花蕾、根、叶、果、茎干、新枝、茎韧皮部、茎皮)中这5种化合物的含量分布情况，并作一比较，为今后建立刺五加质量评价体系提供了科学依据，奠定了坚实的基础。

Plants were hydroponically grown in solutions containing 3 mM Ca(NO3)2 or 3 mM NH4NO3 as nitrogen source. Mature plants were harvested eight times in one day at a 3 hr. interval from 8:00PM Aug. 12 to 5:00PM Aug. 13. Diurnal variations of the shoot nitrate content were observed in either Ca(NO3)2 or NH4NO3 treatment. Shoot nitrate content of Ca(NO3)2 treated plants were higher than those treated with NH4NO3 at every harvest. The average shoot nitrate content of lettuce with Ca(NO3)2 was 0.68% of the dry weight, and it was 0.29% for the NH4NO3 treated lettuce. The fresh weight of the NH4NO3 treated lettuce were 1.43 or 1.2 fold heavier than those with Ca(NO3)2 treatment for shoot or root respectively.

R36品种以3mM硝酸钙(6mM N)或3mM硝酸铵(6mM N)处理，於8月12日下午8点开始采收，每隔3小时采收一次，采收至8月13日下午5点。3mM硝酸钙与3硝酸铵两种养液处理的地上部硝态氮含量皆有日变化，而且在8个采收时间，3mM硝酸钙养液处理的地上部硝态含量皆高於3mM硝酸铵处理。8个采收时间的硝态氮含量平均，3mM硝酸钙养液为乾物含量的0.68%，而3mM硝酸铵处理为0.29%。3mM硝酸铵养液处理的地上部与根部鲜重分别为3mM硝酸钙处理的1.43倍及1.2倍。

More direct, directer ; most direct, directest

径直的，笔直的

Do you know how to use a chain saw?

你知道如何使用链锯吗？