液压翻转开沟覆土犁的设计与研制

为提高液压翻转犁的功能性和作业效率,在借鉴覆土翻转犁技术优势的基础上,设计一种可实现开沟和覆土交替作业的液压翻转开沟覆土犁。液压翻转犁兼具开沟、施肥和覆土功能,能够提高翻转犁的功能性和利用率。     

翻转式鱼鳞坑开沟犁旋转轴受力分析—基于ANSYS

针对3YL-500翻转式鱼鳞坑开沟犁旋转轴的抗弯性能进行了ANSYS分析。首先,根据文献和资料对旋转轴预定了尺寸,并建立了Pro/E三维模型;然后,在ANSYS环境下进行了网格划分和数值计算;最后,得出了旋转轴的Von Misesstress应力云图。对云图进行分析得出了结论:在设计旋转轴时,更应该注意双向犁体与支架的接触位置,只要保证了该位置的抗弯强度,旋转轴就可以顺利承载犁体的升降。     

多向液压调位式开沟犁的研制

开沟犁是农业、林业及水利等工程基本建设中常用于开垦荒地、改造农田、植树造林和修建沟渠的深耕机具,使用中由拖拉机悬挂牵引。但现有产品在耕作过程中存在行距、反土方向及反土量不能自主调节,并且犁体过大、消耗能源多、适用单一和耕作易打乱土层等问题。为此,研制了多向液压调位式开沟犁,其在性能上具有结构简单、一犁多用、液压调位操作、消耗动力小及调位灵活等特点,并可实现翻耕土层不乱的保护性作业。多向液压调位式开沟犁在研制过程中应满足既安全可靠又经济实用的要求。     

1LFT-440型液压翻转调幅犁的设计

铧式犁是世界农业生产中历史悠久、应用最广泛的耕地机械,液压翻转调幅犁是铧式犁中作业效率、自动化水平较高的一种。我国针对不同的作业地区,已设计出不同型号规格的液压翻转调幅犁,但是相比于国外品牌,仍存在作业效果不好、可靠性不高等问题。为此,介绍了一款液压翻转调幅犁关键部件的结构设计,分析了部件强度和整机作业效果,为研制其他型号的液压翻转调幅犁提供参考。     

雷肯翻转犁——迪曼Diamant/欧派EurOpal

在世界上第1台带液压装置的拖拉机刚问世的时候,雷肯就为其生产出配套的液压翻转犁。世界翻转犁的创新和发展潮流一直由雷肯引领。该翻转犁所有关键部件经过世界先进的热处理工艺加工,坚固耐磨损,30多种不同犁体供选择,设和所有的土壤类型。质量小,拖拉机配套性能优秀,耗能低,寿命长,牢固的犁头,能够承受高强度作业。异型钢犁梁结构结实,梁壁厚,十分牢固,该犁梁能够拓展再安装一堆犁体,雷肯翻转犁一大特点是保证翻转犁体质量小,使用寿命长。在德国本土雷肯的翻转犁市场占有率超过65%。     

甘薯起垄整形机犁铧式开沟起垄装置设计与试验

针对现有甘薯起垄整形机起垄效果较差、牵引阻力大等问题,设计了一种甘薯起垄整形机犁铧式开沟起垄装置,并阐述了其主要结构和工作原理。结合甘薯种植模式和垄型结构农艺要求,采用水平直元线法确定了开沟起垄装置犁体曲面的结构参数及其取值范围。运用EDEM离散元仿真软件,建立了犁铧式开沟起垄装置-土壤互作仿真模型。选取开沟犁体曲面安装角、推土角、元线角差值为试验因素,以犁体土壤抛送距离和牵引阻力为评价指标,进行了Box-Behnken中心组合设计试验。仿真试验结果表明,当作业速度为3.33 km/h时,安装角、推土角和元线角差值最优组合为27.19°、38.05°和10.69°。基于优化的最优组合参数进行了田间试验,田间试验结果表明,犁铧式开沟起垄装置垄高稳定性系数为98.53%,垄体土壤紧实度为236kPa,拖拉机作业油耗为11.94L/h,满足甘薯开沟起垄农艺要求,且均优于板式起垄装置作业效果。     

高端液压翻转犁关键技术现状研究

液压翻转犁是世界上应用最广泛的农业耕地机械，其技术水平的高低，在一定程度上反映出农业机械化水平的高低。目前，欧美国家在高端液压翻转犁产品领域处于领先水平，而国内高端液压翻转犁处于起步状态。本文对国外典型高端液压翻转犁关键技术现状进行研究分析，探讨国内液压翻转犁存在的一些问题，提出了我国高端液压翻转犁的发展建议，为国内高端液压翻犁研究开发提供参考。     

1LFT-435型调心调幅式液压翻转犁的研制

针对当前新疆兵团农业生产的需要,研制了一种调心调幅式液压翻转犁,解决了拖拉机和翻转犁配套中出现的漏耕或重耕问题,既可调心亦可调幅,也可同时作用,实现了翻转犁与拖拉机的最优配置,可靠性高、适用性强,适合在农业规模化生产中推广应用。介绍了1LFT-435型调心调幅式液压翻转犁的工作原理、结构特点、试验情况,并分析了应用前景。     

东方红1LF-445/545型液压翻转犁

东方红1LF-445/545型液压翻转犁,是同大型拖拉机配套使用的翻转式耕地机械,适用于大面积农田犁耕作业。主要特点:采用双向液压翻转机构,操作便利、翻垡整齐、降坡效果好;设有小前犁,可切割地表植被     

悬挂式翻转犁的研究现状及发展趋势

犁耕作业是农业生产中必不可少的生产过程,铧式犁也是世界农业生产中历史悠久、应用最广泛的耕地机械。与普通铧式犁相比悬挂式翻转犁在犁架上安装两组左右翻垡的犁体,可以交替工作,减少拖拉机空行程,提高耕地效率。为此,介绍了悬挂式翻转犁的类型及特点,简述了国内外对悬挂式翻转犁的研究现状,分析了我国悬挂式翻转犁在设计发展中存在的主要问题,提出相应的发展对策和建议,从而为我国自行研制适合我国实际情况的悬挂式翻转犁提供参考。     

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。