摘脱割台作物脱粒过程理论分析

论述了割前脱粒水稻收获机摘脱滚筒脱粒的一般过程，并对单株禾杆的脱出过程进行了运动分析，认为作物的脱出过程可为分喂入抽出、冲击脱粒及抛扔阶段。     

纵向轴流脱粒装置的理论模型与仿真

针对新型的纵向轴流联合收割机,研究了其关键部件脱粒装置的工作过程,根据工作过程的分析,从整体的、概率的角度建立了脱粒装置的数学模型,并在计算机上进行了模拟仿真和性能参数的预测．通过仿真分析表明此模型真实地反映了脱粒装置的工作过程,验证了脱粒装置的脱净率和分离率与滚筒长度成指数函数的关系,在滚筒长度达到1．8m时脱粒装置的脱分率最高,较好地满足了技术要求．     

油菜联合收割机脱粒分离装置的试验

为了获得一种适合油菜的脱粒分离装置及其工作参数,首先对油菜部分特性参数进行了测定,然后对纹杆、锯齿型滚筒和栅格、冲孔式组合凹板的脱粒分离装置,在不同喂入量和滚筒转速下进行了油菜脱粒试验．试验结果表明,该装置脱分损失不超过0．5％．运用DPs数据处理系统对试验结果进行处理,建立了油菜喂入量、脱粒滚筒线速度、脱粒滚筒长度与脱粒分离率的回归方程,并进行了计算机仿真．分析表明,脱分率主要与油菜的喂入量、滚筒结构、滚筒线速度和滚筒长度有关,其中滚筒线速度和喂入量对脱分率影响最大．通过试验找到了脱粒分离装置的最佳工作参数．     

切流滚筒细长韧性茎秆防缠绕性能研究

针对脱粒过程中脱粒滚筒被燕麦茎杆缠绕的问题,在保证脱粒滚筒脱粒能力的前提下,设计出了一种新型切流滚筒试验台。通过试验分析,验证了此脱粒滚筒结构设计的可行性与合理性。建立了回归方程,找出最优参数组合,减少了脱粒滚筒缠绕。试验结果表明:切流滚筒在脱粒元件为钉齿式、凹板间隙15 mm、滚筒转速900 r/min时,可有效减少脱粒过程中茎秆的缠绕现象。     

“几何作图法”在联合收割机生产中的应用

4L0．75小型联合收割机，是汉中市收获机械厂旺销了十几年的主导产品。联合收割机的脱粒部分。采用轴流式脱粒机构，作物在滚筒外园与机架顶盖内圆中问旋转2．5N后完成脱粒任务。     

叶轮脱粒机理研究

本文论述了使用高速摄影来研究物料在叶轮式脱粒机构内的工作过程及其在脱粒室内的运动规律,讨论了叶轮脱粒的机理,建立了茎杆物料的运动方程,其结果经试验验证.     

水稻复脱分离系统脱粒分离性能的试验

在传统联合收割机脱粒装置的基础上，设计了适合于梳脱式联合收割机的水稻复脱分离系统的结构参数与工作参数，并在DF-1．5型脱粒分离试验台上进行了性能试验．通过试验得出了脱粒分离性能的轴向变化规律，验证了该新型水稻复脱分离装置的可行性，试验证明设计的装置有助于提高梳脱式联合收割机的整机性能。     

不同湿度作物脱粒的数学模型及最佳参数组合的研究

本文通过作物湿度对传统型脱粒装置脱粒分离性能影响的分析,用三种不同湿度作物进行对比的方法,对传统型脱粒装置脱干燥作物、中湿作物和潮湿作物的脱粒性能进行了试验研究,得出了不同湿度作物下各个性能指标的回归方程,并利用优化技术获得了不同湿度作物的脱粒参数最佳组合方案,对于不同湿度的作物,只要在相应的最佳参数组合方案下进行脱粒,都能获得满意的脱粒性能,提高了传统型脱粒装置对于作物湿度的适应性,为传统型脱粒装置的设计和使用提供了依据。     

免割收获的双行小麦脱粒装置试验

以脱粒总损失率为指标,利用双行小麦脱粒装置试验台,对滚筒转速、齿板厚度和杆齿高度比分别进行单因素试验和对比试验,初步确定了滚筒转速、齿板厚度和杆齿高度比。在此基础上,以脱粒总损失率、含杂率和断穗率为指标,以滚筒转速、脱粒齿排的数量、出口脱粒间隙为试验因素进行了正交试验和回归试验,得到了脱粒装置的最佳参数组合。当滚筒转速为900 r/min、出口脱粒间隙为20 mm、脱粒齿为8排、齿板厚度和杆齿高度比为9∶41、脱粒滚筒长度为650 mm时,脱粒总损失率为4.53%、含杂率为17.39%。     

玉米收获机脱粒装置虚拟样机设计与试验

针对传统玉米收获机脱粒装置设计中试验复杂、研发周期长等问题,以及更好地评价其动力学特性,提出一种基于虚拟样机技术的玉米收获机脱粒装置设计方法.对脱粒装置进行方案设计,确定脱粒滚筒、传动元件等关键部件的相关参数;基于SolidWorks和ADAMS平台创建脱粒装置的虚拟样机模型,根据实际工况添加驱动和负载函数进行仿真分析,结果表明,负载力和力矩的冲击对输入端带轮转速影响小,输出端脱粒滚筒转速响应较快,系统稳定性好,传动效率高,动平衡满足标准要求;通过试验验证了虚拟样机的正确性,可为玉米收获机脱粒装置数字化设计与优化提供参考.     

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.     

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     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with