异向的
- 与 异向的 相关的网络例句 [注:此内容来源于网络,仅供参考]
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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。
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The structure water is dehydrated completely as the temperature is over 1,100 K, the characteristic peak (3,580 cm-1) of the structure water disappears completely, the characteristic peak related to Si-Onb stretching vibration becomes 855 cm-1, which shows that primary Q1 of the hemimorphite is returned to Q0 (i.e [SiO4] ), and which means that the hemimorphite is completely transformed to willemite.
当升温达1 100 K以上,结构水的特征谱峰(3 580 cm-1)消失,与Si-Onb对称伸缩振动对应的特征拉曼谱峰变为855 cm-1,这标志着异极矿原有的Q1结构已完全转变为硅锌矿的Q0结构([SiO4]结构),也就是说异极矿已完成向硅锌矿的转变。关键词:异极矿;原位拉曼光谱;测试;相变;高温
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The wood structures of Lauraceae were characterized by most diffuse porous; most pores solitary, less multiple and cluster pores; simple and scalariform perforation with few bars; most solitary pore; alternate intervessel pitting; most of rays multiseriate, less uniseriate; all of rays heterogeneous, mostly heterogeneous Ⅲ and Ⅱ type rays; most of axial parenchyma paratracheal type, less banded or marginal type; oil cell and mucilage cell in axial parenchyma cell or ray cell; mostly fiber tracheid and libriform fiber, less septate fiber.
结果表明:除檫木外,其它木材的管孔分布均为散孔材,具较高的单孔率;导管分子穿孔板兼有单穿孔和梯状穿孔2种或者仅具有单穿孔;导管间纹孔式为互列;导管-射线间纹孔式类型丰富,主要为刻痕状和大圆状。木射线有单列和多列射线2种类型,单列射线稀少、短,多列射线数量多;射线组织主要为异形Ⅲ和异形Ⅱ;轴向薄壁组织以傍管状为主,少数有带状或轮界状。油细胞和粘液细胞普遍存在于射线薄壁细胞或轴向薄壁细胞中。木纤维由韧性纤维和纤维管胞组成,部分树种具分隔纤维。
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In chapter 6, seven pairs of diastereoisomers of podophyllum lignans at C4-position, including three pairs of spin labeled compounds, were separated by MEKC with 20mM sodium tetraborate-30mM SDS-10% 2-propanol (pH=9.5-9.7) within 20min.
第六章:首次利用胶束电动毛细管色谱分离了七对抗癌药物鬼臼类木脂素在C4位的差向异构体,该方法可用来鉴定分析物的纯度、确定自旋标记化合物C4-H的构型等,为研究差向异构体不同的抗癌机制提供检测手段。
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This social network shows some same characteristics as those of other social networks, such as power law of degree distribution, small world effect, non-trivial clustering or network transitivity, and it also shows the property of assortative mixing which is different from other social networks.
网络呈现了与相关社会网络相似的特性,如度分布的幂律特性、小世界效应、非平凡聚集或网络传递的特点等,同时该网络也表现出与其他社会网络不同的特性,如度的异向匹配。
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Requires extraordinary technical proficiency of the ball, running fast, skilled with the ability to have long-range, and shot a breakthrough technology Qiangdian outflanking shot. In the 1970s, the scope of their duties and activities of a more expanded offensive will no longer be limited to activities within the scope of this position, but often in the middle of the cut, play the role of the center, or with different side of the wing for a wide range of The cross, or retracement from midfield to the role of the avant-garde in order to achieve a variety of effective tactics to attack with.
要求具备熟练的带球过人技术,有快速奔跑、熟练配合的能力,并具备远射、突破射门及抢点包抄射门的技术。20世纪70年代以后,其职责和活动范围更为扩展,进攻时不再仅限于本位置范围内活动,而是经常向中间内切,起到中锋的作用,或与异侧的边锋作大范围的交叉,或回撤至中场起前卫的作用,以实现各种有效的进攻战术配合。
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The strategy involves a staged combustion, where a hydrocarbon fuel added in the second, fuel-rich stage provides hydrocarbon radicals which can react with and finally reduce the NOx formed in the first, fuel-lean stage, such that NOx formed in the first stage reacts with small hydrocarbon radicals present in the second stage combustion, finally leading to N〓, and to HCN which in turn is converted to NO or N〓. Understanding of the chemistry in this second reburning stage is clearly a key to understanding and optimizing reburn technology.
目前消除NOx的主要方法是向燃烧的废气中加入某些化学物质使其重新燃烧(Selective Noncatalytic Reduction of NO processes,SNCR),RAPRENOx过程是SNCR的主要方式之一,其实施是向燃烧产生的废气中加入异氰酸,异氰酸在高温下经一系列包括NCO的自由基反应,可以从燃烧的废气中迅速除去NOx化合物。
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In order to know the evolutionary relationships between false vein, ISC, and VSC in Pteridaceae, 19 grnera and 82 species in Pteridaceae were sampled in this study; silica deposition types, ordinary epidermal cell morphology and veinal epidermal cells morphology of these species were surveyed. On the other hand, a convenient method was developed for this goal. In this method, a tabletop SEM with backscattered electron detector accompanied by post-cooling method was used.
为进一步探讨凤尾蕨科假脉、脉间矽异形细胞与脉上矽异形细胞之间的关系及其於凤尾蕨科内的演化,本论文选取19属82种的凤尾蕨科植物,观察其叶表面之二氧化矽堆积型式、一般表皮细胞形态以及脉上表皮细胞形态;同时,也开发出利用侦测背向散射电子之桌上型扫描式电子显微镜配合后冷却技术(post-cooling method)之快速检测法,该方法利用背向散射电子讯号强弱与平均原子数(average atomic number, Z number)之相关性得到矽异形细胞与一般表皮细胞具有明显对比之影像。
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In these results there are some new findings:(1) when there is not initial geometry defect, multi-waves phenomena still exist and are presented in low orders in vibrative mode shape;(2) of the total vibrative mode shapes of empty tanks there is a type of vibrative mode shapes with the same waves and different directions cos (nθ+φ〓,φ〓≠0 ;(3) the total vibrative mode shape of empty tanks compose of axial symmetry and non-axial symmetry ones corresponding to upright and oblique vibrative mode shape matrices respectively.
最后对空储液罐的特征值问题进行了多达近万自由度的计算分析,得到了一些成果,其中有新的发现:(1)空储液罐的多波现象在无初始几何缺陷时依然存在,而且出现在低阶振型中;(2)在罐的总体振型中存在有同波异向振型(cos,φ〓≠0);(3)罐类的总体振型由轴对称和非轴对称振型组成,并存在相应的正、斜振型矩阵。
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In the first part of this thesis, Stress relaxation method set up in the software of DMA was used to perform the aromatic and aliphalic (D2192-BAPP) PI film stretching process. To study the optical anisotropies property to the light leakage from the crossed polarizers, we put the stretched samples into one set of crossed polarizers and as expected, the stretched PI films could reduce the light leakage at view angle of ±45 deg, and exhibited a visually observed compensating property of an A-plate. No color shift wasobserved, and the birefringence was very uniform. These results prove a uniform birefringence can be obtained by a stretched process for PI films.
首先,我们以动态机械分析仪的应力缓和模式对芳香族FDA-BAPP PI及脂肪族D2192-BAPP PI薄膜进行拉伸实验,并将拉伸后的PI薄膜置於一组相互交差的偏光片中观察其光学异向性,发现拉伸后的PI薄膜试片可以降低在±45o视角的漏光的效果,展现出如同A-Plate的光学补偿特性,所显现的光学补偿效果相当的均匀而且没有色偏的情形发生,证实以拉伸方法可以造成PI薄膜很均匀的双折射效应。
- 推荐网络例句
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By the time of its fall, most of the prisoners were writers who had written against the corruptions of the government.
到它被攻陷的时候,里面多数的犯人是写了反对政府贪污文章的作家。
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The most obvious variation to ovum morphological character was that the color was changed from light green to sepiaceous in embryonic development, and all the ovums were almost hatched after 96h.
在胚胎发育过程中卵的形态特征最明显的变化是颜色从淡绿到深褐色,卵在发育96h后卵基本全部孵化。
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There was a conflict between plebs and patricians in ancient Rome in 494BC.
在公元前494年,罗马发生了一次平民反对贵族的斗争。