华东稻麦轮作区立旋自走电驱动式定角度清秸机设计与试验

传统卧旋式清秸装置动土量较大,且湿黏土壤抛起时易黏附在机器上,导致作业质量下降、油耗增加,影响装置作业稳定性,针对这一问题,设计一种立旋式定角度清秸机,通过结构设计与分析实现清秸刀齿恒定角度作业,避免秸秆二次带回种床,通过对清秸刀齿切土迹距分析确定装置关键结构参数,应用三因素三水平正交试验方法,以作业速度、迹距系数和入土深度为试验因素,清秸率和单位面积作业功耗为试验评价指标,对影响清秸机作业性能的相关参数进行试验与优化。试验结果表明,当参数组合为作业速度4~8 km/h、迹距系数2和入土深度10 mm时,清秸率不小于89.7%、单位面积作业功耗不大于1.84 W·h/m^(2),整个作业过程均未发生土壤黏附现象。研究结果可突破湿黏土壤环境下播种装备作业局限,为稻麦轮作全程机械化提供技术支撑。

稻茬田带状立旋作业参数对种床清秸与平整效果的影响

[目的]本文旨在研究稻茬地秸秆-土壤-带状立式旋耕系统的相互作用机理,探究三者交互作用下关键作业参数对种床清秸与平整效果的影响,为秸秆田间综合管理和水旱轮作系统耕作机械优化设计提供依据。[方法]基于离散元法构建三维立旋仿真模型;模拟水稻秸秆覆盖条件下条带立旋还田作业过程,优化参数范围并进行室内土槽试验验证。以条带立旋作业过程中的前进速度、刀轴转速、秸秆长度为影响因素,以种床清秸率和种床耕后平整度为指标,采用响应面法构建数学模型,分析各因素对种床质量的影响并进行性能优化试验。[结果]在设定耕作深度为15 cm时,影响种床清秸率和种床耕后平整度的主次顺序为前进速度、刀轴转速、秸秆长度。多因素正交试验优化结果表明:机具前进速度1.09 m·s^(-1)、刀轴转速281.5 r·min^(-1)、秸秆长度6.89 cm时种床质量最优,种床清秸率为81.95%,种床平整度为8.67 mm。[结论]本文构建的交互作用模型经验证可靠,能有效评价稻茬田立旋作业参数对种床清秸平整效果。

立旋刀式深松联合耕整地机的设计与试验

深松联合耕整地机是由多种土壤耕作部件组合而成的复式作业机械,适用于北方干旱半干旱地区,以深松为主,兼顾表土松碎,松耙结合,既可用于隔年破除犁底层,又可用于形成上松下实地全面深松,一次进地可以完成深松、灭茬、旋耕等多项作业,提高了效率,降低了成本,减少了机具对土壤的频繁耕作而导致的各种消耗,改善了土壤的物理性质,促进了作物的生长。但是,深松联合整地机作业过程中尚存在土块过大,土层中存在较多较大空隙,不利于作物根系的扎根生长和农田的蓄水保墒。为了提高土壤的蓄水保墒能力,达到较好的松土与碎土效果,在对国内外深松整地机械调研基础上,研制了一种带有立旋刀工作部件的深松联合耕整地机,对深松铲柄、铲头、立式旋刀等主要工作部件进行了结构设计和参数优化。通过田间试验,对免耕(土壤不进行任何处理)、常规深松整地、带有立旋刀的深松联合整地三种不同耕作方式下的土壤坚实度和土壤含水率变化进行测试,并应用Excel 2003,Origin 8.6和SAS 9.2统计分析软件对试验测试结果进行了数据处理与分析,研究结果表明:带有立旋刀的深松联合耕整地机深松>常规深松>免耕,说明研制的带有立旋刀的深松联合耕整地机能有效粉碎的土块,增强土壤的蓄水保墒能力。

立旋式驱动型联合整地机的设计与试验

针对新疆常规联合整地机对黏重土壤播前整地作业耙深稳定性差、碎土率低及地表平整度低等问题,在结合新疆农业对播前整地作业要求、土壤特性等因素的基础上,设计了一种立旋式驱动型联合整地机,并完成整机的加工试制。通过对关键零部件的设计及理论分析,确定了传动系统、平土杠和钉齿镇压辊等零部件的结构参数,并通过运动分析确定耙齿转速为425r/min。为验证整机性能及各项工作参数的准确性,以碎土率、耙深稳定性变异系数和地表平整度标准差为评价指标,在耙齿转速为402r/min、作业深度为100mm、机具前进速度为1.7m/s的条件下对整机进行田间试验。结果表明:碎土率为92.6%,地表平整度标准差为28mm,耙深稳定性变异系数为9.3%,能够满足新疆地区播前整地作业技术要求。

3ZF-3200/3型立旋式马铃薯中耕机的设计与试验

为了解决机械除草过程中马铃薯苗间与秧苗附近杂草较难铲除以及伤苗严重和除净率低等问题,研制出与大功率拖拉机配套的立旋式马铃薯中耕除草机。该文论述了该机具的结构、工艺、工作原理及作业参数,并对该机具关键部件的设计和分析进行了阐述。

立旋打破犁底层试验总结

为深入了解现有的旋耕制度对小麦产量的影响,设计了耕作和灌水裂区试验,研究犁底层对产量的影响和灌水对耕深的补偿作用。结果证明现阶段旋耕技术尚不能对面上的小麦产量水平造成影响。灌水方式较耕作方式对产量的影响更大。试验表明灌挑旗水可有效增加穗粒数,而不增加最大分蘖,是节水灌溉的有用的技术措施。

SLP1060型立旋破碎机的支承设计

SLP1060型立旋破碎机是一种新型的人工砂石制造设备,主轴支承系统是其中关键的部件。对其支承结构的设计和轴承的公差配合、轴承的游隙以及润滑与密封等方面的合理选择进行了论述。

立旋深松耕作对西北半干旱区土壤水分、肥力及马铃薯产量的影响

为探明立旋深松技术对西北半干旱区马铃薯生长、产量以及土壤理化性状的影响,于2018、2019年设置传统旋耕(T)、深翻(D)、立旋深松(V)3个处理,对马铃薯播前、花期和收获期土壤容重、萎蔫系数、田间持水量、碱解氮、速效磷、速效钾、有机质含量及马铃薯的产量进行了研究。结果表明:V处理比T、D处理马铃薯出苗率分别提高3.21%和1.36%,20~40 cm土层土壤容重降低3.6%~12.8%;随着土层深度的增加,3个处理播前、花期和收获后土壤萎蔫系数都逐渐减小,2018、2019年V处理比T、D处理土壤萎蔫系数分别平均降低0.14%、0.14%、0.11%,0.02%、0.06%、0.02%。随着土层深度的增加,不同处理播前、花期和收获后土壤田间持水量逐渐减小,其中V处理在花期和收获期田间持水量分别高于T、D处理1.1%、0.7%和1.0%、0.7%;随着生育期的推进,各处理不同层次土壤养分都有减小的趋势,但收获后V处理各层次土壤养分变化幅度比T和D处理小;2018年和2019年V处理比D、T处理平均增产4.4%和19.1%。

小麦深翻立旋高质量播种技术

针对诸城市小麦玉米两熟制条件下,小麦播种质量不高、抗逆稳产能力弱、产量及效益低的问题,围绕提高秸秆还田质量和播种质量目标,经过多年试验和生产示范,总结集成了一套小麦深翻立旋高质量播种技术,并实现了农机装备的选型和优化,在全市小麦大面积生产中取得了良好的节本增产效果。为加快该技术的推广应用,本文对小麦耕种环节的配套作业机具及各作业环节的作业规范及注意事项等进行了详细阐述,以期为农机手规范化作业,农机生产厂家提高相关机具作业性能和作业质量,保证小麦深翻立旋高质量播种技术效果提供参考。

CUTTING TEMPERATURE MEASUREMENT IN HIGH-SPEED END MILLING

A computer aided measurement system is used to measure the cutting temperature directly in high-speed machining by natural thermocouples and standard thermocouples. In this system the tool/workpiece interface temperature is measured by the tool/workpiece natural thermocouple, while the temperature distribution on the workpiece surface and that of interior are measured by some standard thermocouples prearranged at proper positions. The system can be used to measure cutting temperature in the machining with the rotary cutting tools, such as vertical drill and end milling cutter. It is practically used for the research on high-speed milling with hardened steel.

Lower-Dimensional Volumes and Kastler-Kalau-Walze Type Theorem for Manifolds with Boundary

In this paper,we define lower-dimensional volumes of spin manifolds with boundary.We compute thelower-dimensional volume Vol^((2,2)) for 5-dimensional and 6-dimensional spin manifolds with boundary and we also getthe Kastler-Kalau-Walze type theorem in this case.

Anomalous Hall Effect in Spin-Polarized Two-Dimensional Hole Gas with Cubic-Rashbsa Spin-Orbit Interaction

Based on the Kubo formalism, the anomalous Hall effect in a magnetic two-dimensional hole gas with cubic-Rashba spin-orbit coupling is studied in the presence of δ-function scattering potential. When the weak, shortranged disorder scattering is considered in the Born approximation, we find that the self-energy becomes diagonal in the helicity basis and its value is independent of the wave number, and the vertex correction to the anomalous Hall conductivity due to impurity scattering vanishes when both subbands are occupied. That is to say, the anomalous Hall effect is not vanishing or influenced by the vertex correction for two-dimensional heavy-hole system, which is in sharp contrast to the case of linear-Rashba spin-orbit coupling in the electron band when the short-range disorder scattering is considered and the extrinsic mechanism as well as the effect of external electric field on the SO interaction are ignored.

Vortex-Induced Vibration of Two Parallel Risers:Experimental Test and Numerical Simulation

The vortex-induced vibration of two identical rigidly mounted risers in a parallel arrangement was studied using Ansys-CFX and model tests.The vortex shedding and force were recorded to determine the effect of spacing on the two-degree-of-freedom oscillation of the risers.CFX was used to study the single riser and two parallel risers in 2–8D spacing considering the coupling effect.Because of the limited width of water channel,only three different riser spacings,2D,3D,and 4D,were tested to validate the characteristics of the two parallel risers by comparing to the numerical simulation.The results indicate that the lift force changes significantly with the increase in spacing,and in the case of 3D spacing,the lift force of the two parallel risers reaches the maximum.The vortex shedding of the risers in 3D spacing shows that a variable velocity field with the same frequency as the vortex shedding is generated in the overlapped area,thus equalizing the period of drag force to that of lift force.It can be concluded that the interaction between the two parallel risers is significant when the risers are brought to a small distance between them because the trajectory of riser changes from oval to curve 8 as the spacing is increased.The phase difference of lift force between the two risers is also different as the spacing changes.

Comparison of Carboxylic Acids in Some Crude Oils and Their Diesel Distillates and VGOs:Characterized by Negative-Ion Electrospray Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (Negative-Ion ESI FT-ICR MS)

Three high-acidity crudes, Dar, SZ36-1, and QHD326, were separated through distillation into several fractions, including diesel distillates, and VGOs. Samples were characterized by negative-ion ESI FT-ICR MS. The O2 class species （petroleum carboxylic acids）, which have a close relationship with corrosion of equipment caused by high-acidity crudes, were put in the focus of attention and were discussed in this paper. Monocyclic, bicyclic, and tricyclic naphthenic acids are the main types of petroleum carboxylic acids in naphthenic-base crudes （SZ36-1 and QHD326）. But the main types of petroleum carboxylic acids in paraffinic-base crude （Dar） are aliphatic acids and monocyclic naphthenic acids. The O2 class species in SZ36-1 and QHD326 are distributed in a wider range and have bigger DBE value （double-bond equivalence value） and carbon number than Dar. Bicyclic naphthenic acids have the highest proportion among petroleum carboxylie acids in diesel distillates, but monocyclic and tricyclic naphthenic acids also occupy a high proportion. Particularly, aliphatic acids in the diesel distillate of Dar still have high proportion among petroleum carboxylic acids. The distribution of petroleum carboxylic acids in VGO is basically identical. The bicyclic naphthenic acids assume the first place （about 25 m%）, while the monocyclic and tricyclic naphthenic acids take the next place. The comparison of petroleum carboxylic acids in diesel distillates and VGOs has revealed that the molecules of carboxylic acids in VGOs are not only bigger but also more complicated.

Simulation of Spin-3/2 Blume-Capel Model on a Cellular Automaton with Heating and Cooling Algorithm

The spin-3/2 B1ume-Capel model is studied using the heating and cooling algorithms improved from the Creutz cellular automaton （CCA）. The calculations are done on various sizes of the simple cubic lattice in the 0 ≤ D/J ≤ 5 parameter region. The phase diagram of the model and temperature variation of the thermodynamic quantities are obtained. We confirm the existence of a critical end point within the heating calculations. However, in contrast to the heating calculations, we do not obtain the first-order line at low temperature with cooling algorithm calculations. The results are compared with those of other theories.

Soliton dynamics in planar ferromagnets and anti-ferromagnets

The aim of this paper is to present a rigorous mathematical proof of the dynamical laws for the topological solitons( magnetic vortices) in ferromagnets and anti-ferromagnets. It is achieved through the conservation laws for the topological vorticity and the weak convergence methods.

Dating of the topmost terrace in the Jingxian Basin,Anhui Province:an indication of the establishment of the Qingyijiang River

On the northern fringe of Mt. Huangshan, many fiver terraces are developed at the junction between mountains and plains. The fiver terraces are most typical in the Jingxian Basin, Anhui Province, where the Qingyijiang River, one of the longest tributaries of the lower Yangtze River, developed three staircase terraces. The topmost terrace （i.e., the T3 terrace） tread is 38 - 39 m above fiver level, and the top of the gravels is generally covered by 3 - 10.9 m of red clay deposits. Systematic magnetostratigraphy and electron spin resonance dating are used to research the timing of the establishment of the Qingyijiang River. The main results show that the topmost terrace developed no later than 900 kyr ago and that the appearance of the Qingyijiang River occurred correspondingly at least before 900 kyr ago on the northern fringe of Mt. Huangshan. In view of the almost synchronous age,the establishment of the Qingyijiang River was seemingly a response to the Mid-Pleistocene Revolution when the 100 kyr cycle commenced, and the Kunlun-Huanghe movement during the early- middle Pleistocene transition. In addition, the establishment of the Qingyijiang River possibly reflected the birth of the modem Yangtze River to some degree. Therefore the timing of the formation of the Yangtze River is restricted to no later than 900 kyr ago based on the appearance of the Qingyijiang River .

Distribution of Carboxylic Acids in Sudanese Dar Crude Oil: Characterized by Negative-Ion Electrospray Ionization Fou- rier Transform Ion Cyclotron Resonance Mass Spectrometry

The Dar crude oil produced in Sudan was distilled into several fractions. The heteroatom class species in crude and its fractions were characterized by the negative-ion ESI FT-ICR MS. The major emphasis was put upon the study on the O2 class species (petroleum carboxylic acids). The test results revealed that aliphatic acids and monocyclic naphthenic acids accounted for a large proportion in petroleum carboxylic acids of the Dar crude. The relative abundance of aliphatic acids and monocyclic naphthenic acids decreased with an increasing boiling point of fractions. Meanwhile, the relative abundance of bicyclic and tricyclic naphthenic acids increased at first and then decreased, whereas the relative abundance of petroleum carboxylic acids with higher double-bond equivalence (DBE) values increased. The high abundance of aliphatic acids in the Dar crude and its fractions covered the carbon numbers in a range of 16 to 18 which had important geochemical signifi- cance. The O2 class species were distributed in a broad range of DBE values and carbon numbers with increasing boiling points of fractions.

Measuring Propeller Blade Width Using Binocular Stereo Vision

Propeller blade width measurement has been extensively studied in the past using direct and indirect methods, and it plays a great role in determining the quality of the finished products. It has surveyed that previous techniques are usually time-consuming and erroneous due to a large number of points to be processed in blade width measurement. This paper proposes a new method of measuring blade width using two images acquired from different viewpoints of the same blade. And a new feature points matching approach for propeller blade image is proposed in stereo vision measurement. Based on these, pixel coordinates of contour points of the blade in two images are extracted and converted to real world coordinates by image algorithm and binocular stereo machine vision theory. Then, from the real world coordinates, the blade width at any position can be determined by simple geometrical method.

Magnetic Properties of Transverse Ising Model under a Time Oscillating Longitudinal Field

A transverse Ising spin system, in the presence of time-dependent longitudinal field, is studied by the effective-field theory （EFT）. The effective-field equations of motion of the average magnetization are given for the simple cubic lattice （Z ---- 6） and the honeycomb lattice （Z = 3）. The Liapunov exponent A is calculated for discussing the stability of the magnetization and it is used to determine the phase boundary. The dynamic phase transition diagrams in ho/ZJ - F/ZJ plane and in ho/ZJ - T/ZJ plane have been drawn, and there is no dynamical tricritical point on the dynamic phase transition boundary. The effect of the thermal fluctuations upon the dynamic phase boundary has been discussed.