香蕉免耕地深松铲的设计与有限元分析

针对我国热带农业区香蕉地长期翻耕,土壤板结严重、肥力下降等问题,本文研究了一种基于免耕技术的香蕉地深松铲.主要设计了深松铲尖、深松刀刃和深松侧翼等关键部件,并确定了其主要结构参数.利用Pro/E三维软件、Hyper mesh和ABAQUS软件对深松铲进行外部结构研究和有限元强度校核,验证了该深松铲应用于我国热带农业区香蕉免耕地深松作业的可行性.     

悬挂式多功能耕整联合作业机的工作原理及应用

在概述深松耕法的原理及优势基础上,介绍一种有利发挥深松作业效果、由多种工作部组成的联合作业机具——多功能耕整联合作业机。该机是一种既适于垄作,又可用于平作、单独超深松、起垄、趟地作业的多功能机具,具有结构简单、工作可靠、效率高、一机多用等优点。     

1SBL-350型耙茬深松整地机的研究

针对国内农业机械中深松整地机作业现状,在吸收国内外深松整地技术的基础上,研发了一种新型耙茬深松整地机。介绍该整地机的总体结构和工作原理,并分析主要工作部件的设计结构,该机性能可靠、作业效果好。     

深松铲对砖红壤扰动行为影响的仿真与试验

针对香蕉地深松作业相关研究较少，深松铲-土壤耦合机理尚未明确等问题，结合海南热区香蕉地砖红壤土的物理特性，利用离散元虚拟仿真试验，堆积生成了耕作层、犁底层和心土层3层土壤模型，建立了滑切深松铲-土壤耕作模型，并通过对比虚拟仿真试验，研究了滑式深松铲和国标深松铲对海南香蕉地土壤的扰动情况。结果表明：在相同的作业条件下，滑式深松铲作用下的土壤颗粒在x、y和z方向的最大运动速度均明显大于国标深松铲对土壤颗粒的作用，且滑式深松铲的扰动轮廓要明显大于国标深松铲作业的扰动轮廓，同时滑式深松铲作用下土壤蓬松度和土壤扰动系数均大于国标深松铲作用产生的深松效果，进一步验证了所设计的滑式深松铲更适用于海南香蕉地的深松作业。     

现代农业下新型智能深松机研究试验

本文主要针对深松作业时深松深度难以达到预设深度,无法起到深松效果,深松作业面积测量起来费时费力,投入的监管人员多,且作业数据难以长久保存的问题,而设计的一种智能化控制系统,用于对农田深松作业进行监管;目前市面上存在的传统深松作业所需能耗较大、耕作阻力大,主要原因是深松铲的形状、结构及其参数不合理,优化的新型深松铲,可以很好地完成保护性耕作——深松作业。     

基于离散元法的砖红壤斜柄折翼式深松铲设计与试验

针对深松整地装备应用于海南省热带农业区香蕉地时,存在作业阻力大、松土面积小及地表平整度差等问题,本文基于海南香蕉地砖红壤土的物理特性,设计一种可有效降低作业阻力的斜柄折翼式深松铲.运用离散元法建立3层土壤颗粒虚拟仿真土槽模型,使用Hertz-Mindlin with JKR接触模型进行了斜柄折翼式深松铲与直柄凿式深松铲...     

1SBL-360松耙联合整地机的设计与试验

为了满足深松和耙地同时作业的需求,在吸收国内外先进技术基础上,创新研究设计了集深松、耙地、碎土于一体的松耙联合整地机,该机主要由切草装置、弧形深松铲和圆盘耙组组成.通过作业实验机具性能,结果表明该机具具有作业效率高、节约能耗、降低成本、作业效果好等优点,深松耙地作业后的各项性能指标均能满足作业标准的要求.     

1SX-3000型深松机设计与试验研究

长期不合理耕作方式导致土壤结构性能恶化，严重影响着土壤质量及作物的产量和品质，已成为制约我国农业可持续发展的重要问题。深松作业是保护性耕作的重要内容之一，也是土壤耕层构建的重要方式，其特点是耕作时超过常规耕层深度而不打乱上、下土层，是农业生产过程中重要的增产技术措施。深松作业可以打破犁底层并改善土壤透水、透气性能，为植物根系提供良好的生长环境。为此，针对深松作业阻力大、土壤松碎效果差的难题，借鉴国内外的深松技术研究成果，设计了一种深松作业机具，旨在为深松机的设计提供理论依据和技术支撑。田间试验表明：该机深松深度变异系数平均值为6.88%,深松深度稳定系数平均值为93.12%,碎土率平均值为37.07%,土壤蓬松度平均值为35.59%、土壤扰动系数平均值为53.07%,各项测试指标均能满足相应的国家标准，机具性能可靠，作业效果满足设计要求。     

灭茬深松旋耕起垄机的研究

在原有灭茬旋耕机的基础上,增加深松功能,设计一种新型的灭茬深松旋耕起垄机。介绍该机的整体结构和工作原理,阐述机具主要部件的设计方案。该机一次进地可完成灭茬、深松、旋耕、起垄、镇压等联合作业,能够有效打破犁底层,改善作物生长的土壤条件,具有一定的推广价值。     

1LH-350型深松机的研制

针对国内现有深松机普遍存在深松深度浅、耕作阻力大、作业易堵塞等问题,结合黑龙江省的土壤状况和耕作模式,研制了一种悬挂式深松碎土机。主要介绍该机具总体结构与关键部件的设计,通过性能试验,该机能够保证打破犁底层同时又不翻乱土层,使耕后土层形成上虚下实、虚实相间的结构,为农作物生长提供良好的土壤条件。     

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.     

车用发动机润滑油失效规律与更换周期研究

研究在正常使用条件下１０Ｗ／３０－ＱＣ级润滑油用于某型车用发动机时所表现的失效规律,确认期服从两参数Ｗｅｉｂｕｌｌ分布,并给出分布的尺度参数η和形状参数ｍ之最佳线性无偏估计（ＢＬＵＥ）同时,还为定量分析,计算车用发动机润滑油的使用可靠性和合理确定其更换周期提供了一套可供借鉴的方法,并给出了具体的计算实例。     

农村剩余劳动力就业问题的探讨

论述了我国农村剩余劳动力就业的意义,并针对我国农村剩余劳动力的现状,提出多渠道促进农村剩余劳动力就业的途径和办法。     

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。     

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。     

乡（镇）农业技术推广体系存在的问题及对策

乡（镇）农技推广体系是农业发展的关键。介绍朝阳市农业技术推广体系的现状,针对目前体制及运行机制、服务手段等方面存在的问题,提出适合朝阳市乡（镇）农技推广体系改革与发展的对策,以期对全省农技推广体系改革和发展起到一些借鉴作用。     

草莓的采收与贮藏

草莓果味酸甜爽口,营养价值高,为人们所喜爱的应市鲜果之一。由于草莓易受损伤和微生物侵染,因此其采收、贮藏过程极为重要。介绍草莓采收过程中的注意事项以及11种贮藏保鲜技术的实施步骤和操作方法,推介9种加工方式,为草莓产业化提供技术支持。     

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。     

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.