油葵联合收获机专用割台设计与试验

针对国内现有油葵联合收获机割台存在的物料堵塞、堆积以及因拨禾轮回带导致的葵盘无法进入割台等问题,结合我国油葵种植模式和农艺要求,设计了一种拨禾轮式油葵联合收获机专用割台。对分禾过程中油葵茎秆的姿态进行分析,确定了内分禾器宽度、长度和内分禾器间隙;选取不同拨禾速比λ,对拨禾轮运动轨迹进行仿真分析,确定了拨禾速比取值范围,并得出拨禾轮的最优直径和转速;为降低输送器输送时拨指对葵盘的击打和油葵茎秆的缠绕,设计了刮板式输送器;为保证良好的切割效果,基于刀机速比γ,确定了往复式切割器切割速度。在新疆维吾尔自治区阜康市河南庄子村进行了油葵收获田间试验,当整机前进速度为0.8 m/s时,喂入量为3.3 kg/s,割台平均损失率仅为1.42%,整机作业效率0.69 hm~2/h。收获作业过程中整机运行平稳,割台收获过程无堵塞、无缠绕,满足油葵联合收获机割台的设计要求。     

沙生灌木平茬机切割器刃口曲线的设计

通过分析沙生灌木平茬机切割器的切割方式和运动规律,提出了用等滑切角曲线方程设计刃口曲线形状的方法,以30°和53°的滑切角为参数设计制造了割刀。室内外切割对比试验表明,等滑切角曲线刃口割刀的切割效果要优于直线刃口割刀的切割效果。     

甘薯秧蔓收获机专用割台设计与试验

针对甘薯分段收获技术需求,结合国内外甘薯收获技术及装备,提出一种甘薯秧蔓收获方式,并设计甘薯秧蔓收获机专用割台。该甘薯秧蔓收获割台主要由拨禾切割装置和防堵防缠输送装置组成,可以实现甘薯秧蔓的切—送—归集。首先,理论分析该割台的关键部件结构参数及传动配置关系,确定拨禾切割装置上仿垄型排列的割刀和弹齿的安装高度和安装密度,以及拨禾轮、割刀和弹齿的结构参数。其次,通过对拨禾切割装置、捡拾装置和螺旋输送装置进行运动学和力学分析,明确拨禾轮、捡拾器、螺旋输送绞龙转速和结构决定秧蔓切割效果和收获质量,并确定捡拾器和螺旋输送绞龙的关键结构参数,最后进行田间试验验证该机具的切—送—归集收获效果。结果表明：当整机前进速度为0.6 m/s,拨禾轮转速为46 r/min,捡拾器转速为43 r/min,割台损失率仅为1.3%,整机作业效率为0.45 hm²/h。割台搭配48 kW拖拉机在工作过程中运行稳定,割台在工作过程中无堵塞、无缠绕,满足甘薯秧蔓联合收获机的设计需求。     

工业大麻小型立式割台切割器运动分析与仿真

切割器是割台的关键核心部件,其工作性能直接影响割台的工作效率,设计一种工业大麻往复式切割器,进行切割器的运动学原理和动力学分析,并应用Adams软件直观地分析切割器工作过程中割刀的位移、速度和加速度的变化规律,并得到切割过程中切割力变化规律。仿真结果表明切割器的运动规律与实际基本相符,该机构设计合理。     

4QM-4.0型麻类青饲料联合收获机割台结构设计与试验

针对现有牧草收割机收割饲用苎麻作物时，割台输料不畅，搅龙易被麻类纤维缠绕的问题，设计一种专用收割机割台。该割台由往复式切割装置、拨禾轮、茎秆捡拾输送器及螺旋搅龙组成。根据饲用苎麻的田间生长特性及物料特点，开展收割机割台设计。通过理论计算与试验分析，确定割台各关键装置结构参数：拨禾轮的圆周半径为840 mm、切割器离拨禾轮轴高度为1 470 mm、拨禾轮转速27.9 r/min、升降行程为700 mm、往复式割刀曲柄转速为540 r/min、茎秆捡拾输送器拨齿轮滚筒半径为150 mm、转速为152.80 r/min，喂入搅龙直径为320 mm、转速为170 r/min。田间试验表明：该机收获损失率为3%，标准草长率为91%，作业小时生产率为0.25~0.35 hm2/h，割茬高度为150 mm。收割时，割台未出现堵料及纤维缠绕现象；收割后，苎麻割茬整齐，未发现作物茎秆基部存在明显撕裂现象。试验结果表明往复式切割器切割效果良好，整机工作性能稳定，该收割机割台能够满足对饲用苎麻作物的收割要求。     

油葵收获割台设计与试验研究

针对目前我国油葵收获机械化程度低,严重依赖人工导致效率低、劳动强度高等问题,结合华北油葵的种植模式,设计了一种油葵收获割台,确定了割台的整体方案及工作方式。该割台主要由机架、分禾器、拉茎辊、拨禾喂入装置、葵盘接穗装置和输送搅龙等组成,能够实现下拉并切割茎秆,减轻葵盘与接穗板间的撞击,减少籽粒的损失,最终只收获葵盘和与其连接的少许茎秆。田间试验结果表明:割台工作稳定,工作性能满足油葵收获的需求。同时,就割台在收获过程中存在的问题进行总结分析并提出相应解决措施,为油葵割台的后续研发提供了理论基础和应用实例。     

油菜联合收割机割台损失影响因素的试验研究

对油菜收割台的结构特点进行了理论分析,然后通过改变拨禾轮转速、机器前进速度、拨禾轮轴相对割刀的位置等影响割台损失的因素进行试验分析。通过单因素试验寻找各因素与割台损失的影响规律,通过正交试验得出了机器前进速度对割台损失影响最为显著,其次为拨禾轮转速。运用DPS数据处理系统对试验结果进行处理,建立了拨禾轮转速、机器前进速度与拨禾轮轴相对割刀垂直位置的回归方程,并对模型进行参数优化得到了最佳工作参数与结构参数。     

小区谷物联合收获机割台设计与试验研究

在对现有收获机割台的设计原理和优缺点进行对比分析的基础上,设计了拨禾轮齿带毛刷清扫、风吹清种、中间喂入、环形橡胶输送带柔性输送的卧式全喂入割台,避免金属制输送器对种粒的挤压损坏和易残留问题,实现种子收获时降低破损率和混种率的目的。对割台各部件进行形式对比和计算分析,得到最佳割台组合形式。为避免收获过程中受割刀机构的惯性不平衡力、切割作用的冲击载荷、拨禾轮和割台输送机构等运动元件载荷引起的共振,对设计完成的收获割台底架进行了模型分析,保证了割台底架形式的有效性。运用回归分析试验设计方法,对割台拨禾装置建立了数学模型,并进行了优化分析处理,为小区育种机械化收获技术提供了理论与技术支持。     

前驱苜蓿刈割压扁机切割装置设计与分析

针对苜蓿刈割压扁机在作业过程中出现的收获质量低、漏割率高、割茬高度不一致等问题,基于苜蓿收获要求,设计了一种前驱苜蓿刈割压扁机的切割装置。对其核心作业部件完成理论设计并确定相关结构和参数,对割刀进行运动学和动力学分析,并基于ADAMS软件对切割器在复杂路面的工作性能进行仿真。研究结果显示:刀盘转速为1800r/min和割刀数量为8片时,能够确保刈割作业不发生漏割现象;切割扭矩主要取决于刀盘转速和割刀刃长;所设计的切割器在复杂路面作业具备良好的通过性,可以保证割茬高度一致。研究成果可为苜蓿刈割压扁机的设计与优化提供参考。     

9 GSCC-1.4 H水草收割机切割装置改进设计

9GSCC-1.4H水草收割机往复式切割装置不同于牧草收获机械切割装置,其割刀传动装置位于切割器的后面,且曲柄连杆与水平面成一定角度,割刀传动零件拨叉主动臂与从动臂不在同一平面内,切割过程中拨叉与动刀组拨杆接触的运动轨迹为空间弧线的线接触,同时在拨叉和拨杆间有冲击振动,加快了拨叉与拨杆的磨损,缩短了切割装置的使用寿命.为此,对9GSCC-1.4H水草收割机切割装置进行了动力学分析,针对切割装置存在的问题,对割刀传动装置进行了结构改进设计:将拨叉从动臂改为摇杆,曲柄连杆与小拨叉铰接,小拨叉通过中间连杆驱动摇杆往复摆动,小拨叉和中间连杆用球轴承连接消除空间曲线轨迹对连杆的作用,摇杆驱动切割器实现往复切割运动.     

Overland water and salt flows in a set of rice paddies

Cultivation of paddy rice in semiarid areas of the world faces problems related to water scarcity. This paper aims at characterizing water use in a set of paddies located in the central Ebro basin of Spain using experimentation and computer simulation. A commercial field with six interconnected paddies, with a total area of 5.31 ha, was instrumented to measure discharge and water quality at the inflow and at the runoff outlet. The soil was classified as a Typic Calcixerept, and was characterized by a mild salinity (2.5 dS m⁻¹) and an infiltration rate of 5.8 mm day⁻¹. The evolution of flow depth at all paddies was recorded. Data from the 2002 rice-growing season was elaborated using a mass balance approach to estimate the infiltration rate and the evolution of discharge between paddies. Seasonal crop evapotranspiration, estimated with the surface renewal method, was 731 mm (5.1 mm day⁻¹), very similar to that of other summer cereals grown in the area, like corn. The irrigation input was 1874 mm, deep percolation was 830 mm and surface runoff was 372 mm. Irrigation efficiency was estimated as 41%. The quality of surface runoff water was slightly degraded due to evapoconcentration and to the contact with the soil. During the period 2001–2003, the electrical conductivity of surface runoff water was 54% higher than that of irrigation water. However, the runoff water was suitable for irrigation. A mechanistic mass balance model of inter-paddy water flow permitted to conclude that improvements in irrigation efficiency cannot be easily obtained in the experimental conditions. Since deep percolation losses more than double surface runoff losses, a reduction in irrigation discharge would not have much room for efficiency improvement. Simulations also showed that rice irrigation performance was not negatively affected by the fluctuating inflow hydrograph. These hydrographs are typical of turnouts located at the tail end of tertiary irrigation ditches. In fact, these are the sites where rice has been historically cultivated in the study area, since local soils are often saline-sodic and can only grow paddy rice taking advantage of the low salinity of the irrigation water. The low infiltration rate characteristic of these saline-sodic soils (an experimental value of 3.2 mm day⁻¹ was obtained) combined with a reduced irrigation discharge resulted in a simulated irrigation efficiency of 60%. Paddy rice irrigation efficiency can attain reasonable values in the local saline-sodic soils, where the infiltration rate is clearly smaller than the average daily rice evapotranspiration.     

瓦房店市水果生产标准化发展研究

瓦房店市是我国重要的水果生产基地,在国内水果生产领域占有重要地位。随着水果市场化的不断深入,如何满足和适应国内外市场需求成为瓦房店市水果生产的关键问题。从瓦房店市水果生产实际出发,阐述了实施水果生产标准化的必要性,提出了发展水果生产标准化的具体措施。     

金谷子耐旱TG118引种试种及推广应用

对引进的谷子新品种金谷子耐旱TG118进行品种比较试验和多点试种。结果表明：该品种抗旱、耐瘠、适应性强,稳产、高产、抗病抗风抗倒伏强,品质优良,粮草兼用,种植简单,省工易管;一般产量在6000kg/hm2以上,比当地主栽品种增产20%以上。最高产量达9450kg/hm2,适于在辽西北地区推广应用。     

对《种子法》存在问题的探讨

《种子法》是我国种植业第一部法律。自实施以来,为依法加强种子管理提供了有力的法律支撑,促进我国种子产业发生翻天覆地的变化。但随着依法管理工作的深入和种子产业的快速发展,《种子法》及配套规章的一些问题逐步显现出来。对《种子法》及配套规章存在的问题进行深入分析,对需要进一步补充的章节以及需要调整的内容进行深入探讨,以求更加完善和明确。     

Review of the Egyptian experience in implementing land drainage projects

About 30 years have passed since the Government of Egypt embarked on implementing a series of large scale drainage projects. At present, about 3.8 million acres have been provided with drainage systems on the basis of systematic pre-drainage investigations and designs. The target is to provide drains in approximately 6.4 million acres in the Nile Valley and Delta.The implementation of the subsurface drainage system is carried out by the public sector and private contractors under direct supervision of governmental regional departments. The implementation process depends on many factors related to the drainage material, machinery, manpower, site requirements, farmers and organizations involved. Problems and constraints are sometimes challenging, however, the annual rate of implementation has gradually increased to 170,000 acre/year.This paper discusses the different aspects involved in the implementation process of drainage systems. The development in materials, machinery and construction technologies will be reviewed. Institutional and management factors are going to be also considered.     

和谐社会理论建设的几点哲学思考

在新世纪,面对机遇和挑战,党的十六大把“社会更加和谐”作为全面建设更高水平的小康社会的一个重要目标。中国人素有社会和谐的理想;西方人自古也向往社会和谐;借鉴东西方两种和谐社会思想的经验、教训,构建社会主义和谐社会理论。     

A European irrigation map for spatially distributed agricultural modelling

We present a pan-European irrigation map based on regional European statistics, a European land use map and a global irrigation map. The map provides spatial information on the distribution of irrigated areas per crop type which allows determining irrigated areas at the level of spatial modelling units. The map is a requirement for a European scale assessment of the impacts of irrigated agriculture on water resources based on spatially distributed modelling of crop growth and water balance. The irrigation map was compiled in a two step procedure. First, irrigated areas were distributed to potentially irrigated crops at a regional level (European statistical regions NUTS3), combining Farm Structure Survey (FSS) data on irrigated area, crop-specific irrigated area for crops whenever available, and total crop area. Second, crop-specific irrigated area was distributed within each statistical region based on the crop distribution given in our land use map. A global map of irrigated areas with a 5′ resolution was used to further constrain the distribution within each NUTS3 based on the density of irrigated areas. The constrained distribution of irrigated areas as taken from statistics to a high resolution dataset enables us to estimate irrigated areas for various spatial entities, including administrative, natural and artificial units, providing a reasonable input scenario for large-scale distributed modelling applications. The dataset bridges a gap between global datasets and detailed regional data on the distribution of irrigated areas and provides information for various assessments and modelling applications.     

粉质仪和拉伸仪在面粉生产中的应用

在介绍粉质仪和拉伸仪结构和原理的基础上,探讨了粉质曲线中吸水率、形成时间、稳定时间、弱化度和评价值等指标与面粉品质的关系,以及如何根据拉伸曲线中面团最大拉伸阻力、延伸度和拉伸曲线面积等指标来评价面团品质,并结合生产实际,概述了粉质仪和拉伸仪在面粉生产中的作用。     

农村信息化服务的现状及建设措施

分析当前我国农村信息化服务的现状,提出加强农村信息化服务的新举措。     

车辆ABS控制算法的研究及探讨

对现代汽车的ABS控制算法作了一些简单的介绍,同时指出了它们的一些缺陷,相应地提出了几种对ABS的其它控制方法并加以探讨,其中着重论述了ABS门限值控制算法中参考车速的确定方法和基于附着系数的控制算法。