矿用链条、刮板、链轮、中部槽标准化研究

本文介绍了国内外矿用链条、刮板、链轮、中部槽的标准现状,并介绍了神东煤炭集团如何制定矿用链条、刮板、链轮、中部槽及相互之间的配套等标准情况,重点介绍了采取的工作措施和关键技术研究情况,阐述了制定链条、刮板、链轮、中部槽等标准的意义,提出了标准下一步发展建议。     

新型滚子链的设计方法及其啮合分析

为了减小链传动过程中的啮入冲击、振动和噪声,设计了一种新型滚子链机构.模拟链轮与链条的相对运动过程,把滚子作为假想刀具,利用AutoCAD的二次开发工具ObjectARX进行编程,由滚子的运动轨迹包络出链轮的齿形.建立了采用新型链轮的滚子链传动系统的动力学模型,可以精确地模拟滚子链系统的工作过程.对标准滚子链传动系统和...     

刮板输送机链轮瞬态动力学响应分析

对刮板输送机链轮与圆环链在平稳运行工况下进行瞬态动力学分析,得出了链轮在典型姿态下的应变响应,以及链轮链窝关键位置的应变历程、法向力历程和切向力历程.通过分析得知,链轮与圆环链啮合过程中链轮承载不均匀,链轮与圆环链之间会产生明显的滑动现象;圆环链的底面与链轮链窝底平面之间存在间隙,这会加剧链轮表面的磨损和压溃.针对这些问题,分别给出了相应的改进措施,改进后可以延缓链轮的磨损和压溃,提高链轮的使用寿命.     

SGZ-1000/2×700型刮板运输机链轮组件修理探讨

铁能公司本部八个生产矿井综采工作面常用的SGZ系列刮板运输机机型有SGZ-800/2×400型、SGZ-1000/2×700型、SGZ-1000/2×855型、SGZ-1000/2×1000型,运输机的链轮组件是运输机重要部件,链轮组件的链轮齿磨损、密封漏油、轴承间隙超差等故障是链轮组件在井下工作面使用过程中的常见故障。对链轮组件进行修复使用,是降低煤炭生产成本的重要措施。本文以SGZ-1000/2×700型刮板运输机链轮组件修理为例,对修理工艺进行了详细的分析、探讨,为其他机型的链轮组件修理提供了参考性经验。     

基于ANSYS的外摆线链轮的模态分析

为了提高链轮工作的可靠性,应避免链轮在传动系统中发生共振.根据链轮外摆线齿廓的形成原理,通过圆族包络法,得到实际链轮齿廓方程.然后利用Pro/E建立链轮的三维模型,并导入ANSYS软件对链轮模型进行模态分析,确定了摆线链轮固有频率和振型,从而避免链轮在传动过程中发生共振现象,同时为链轮的进一步优化设计提供技术参考.     

离散化分析不同运行状态下刮板输送机链轮传动系统动力学

链轮传动系统是刮板输送机最关键的系统之一。为了改善刮板输送机链轮传动系统的动力学性能,提高整台刮板输送机的运输性能,对刮板输送机链轮传动系统的动力学进行研究。以大功率刮板输送机为研究对象,通过有限元法离散化分析在不同运行状态下刮板输送机链轮系统动力学。首先离散化刮板输送机链轮,将其划分为若干不同单元,构建链轮传动系统的有限元方程。分别得到机头、机尾链轮的驱动转矩、链条的预紧力及链环和链轮啮合的动力学方程。对大功率刮板输送机链轮传动系统在不同状态下(起/制动、恒速运行和异常载荷状态下)的动力学特性进行研究,获取其机头、机尾等的变化情况,为链轮传动系统的优化提供依据。     

传动链轮齿形的探讨——对国内有关链轮标准内容的商榷

本文对现行的主要国际标准及国家标准中有关链轮方面的某些规定提出异议、商榷,旨在完善和提高标准的质量。所研讨的主要内容有: 1.传功用链轮的Seating Curve具有特别重要的作用,它有别于其他用途的链轮。 2.论证了Seating Curve与压力角及最小齿数间的关系。从而证明了在ISO1275中规定的最少齿数为5是不妥的,因为那将导致压力角可能出现负值,而这是不容许的。 3.对最大齿廓形状与最小齿廓形状指出完整的概念。 4.对于链轮齿高的准确理解。 5.关于有关公差的准确要求问题。     

导磁体对链轮感应加热过程影响的研究

链轮复杂的结构增加了感应加热时控制磁感应强度分布的难度,严重影响着轮齿加热层温度的均匀性,制约淬火效果的提升。导磁体作为调控磁场分布的重要手段,可显著提高链轮感应加热的质量。但是,目前导磁体对链轮感应加热过程的影响未进行系统的研究。本文采用导磁体配合V形线圈对链轮进行感应加热,并通过有限元模拟系统地分析了导磁体结构参数对链轮感应加热过程的影响规律。研究发现：不同导磁体结构参数对温度均匀性的影响规律不同,并且导磁体侧板圆半径的改变对链轮感应加热温度均匀性的影响最大,导磁体侧板夹角的改变对链轮感应加热温度均匀性的影响最小。     

评标准《ZB J81 008.1—89》(悬挂输送机牵引可拆链)及《ZB J81 008.2—89》(悬挂输送机 链轮)——关于我国链条标准评述之一

1.对于悬挂输送机用可拆链及链轮的结构特征,力学性能作了深入分析 2.对于相应标准中的缺点和错误作了全面评述 3.对于修订和完善标准等提供了原则设想     

FP2500A型翻抛机关键零部件有限元分析

利用人畜粪便、农作物秸秆、污泥及其它废弃物生产有机肥具有重要意义.有机肥翻抛中用工量最大的是翻抛作业.刮板和主动链轮是翻抛机的主要零件.利用三维建模软件Pro/E建立刮板和主动链轮模型,导入有限元分析软件ANSYS对其进行静力分析,得到刮板和链轮的等效应力云图和等效位移云图.其分析结果为刮板和主动链轮的进一步优化设计提供了理论依据.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that