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宁明县农民集资4000余万元办农机宁明县广大农民选择了适应当地条件的主要农机经营形式——以户营小型农机为主,大大激发了农民办机械化的积极性,改“出大力流大汗”为靠机械靠技术致富。到今年7月底全县已有6300多户农民集资4580多万元,购买了拖拉机、柴... 相似文献
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根据使用现状,拖拉机一般既遭受有形磨损,又遭受无形磨损,并且维修开始趋于视情维修。在生产实际中,拖拉机更新基本上还是属于同型更新(这里所谓“同型”是指机器的功能、原值差别不太大)。在此大背景下,阐述了拖拉机经济寿命计算时的目标选择问题,并给出了不同目标下拖拉机经济寿命的计算模型。这些新的模型为进一步研究拖拉机经济寿命提供了新思路。 相似文献
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拖拉机田间作业的最佳功率 总被引:7,自引:2,他引:5
本文从运用机器的技术经济观点出发,建立以年总作业时T(或年田间作业量S)、作业小区垄长L和主机标定功率N_(en)等一系列结构和运用参数为自变量,以机组作业成本为函数的数学模型,能比较准确地模拟各种使用条件下的机组作业成本,从而可对各种机组的作业经济性作事先的比较;并应用优化方法得出同一类型拖拉机在一定的使用条件下作业,要使总成本最低时所对应的标定功率,可为因地制宜地选择田间作业经济性最好的拖拉机提供定量的分析方法和依据,也为配套最佳的机群结构提供了依据。 相似文献
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柳忠琴 《农业机械化与电气化》1995,(6)
邓小平同志指出“科学技术是第一生产力”。“农业要实现科技兴农,加快农业生产力水平的发展”。农民奔小康的步伐越来越大,然而对科学技术知识的需求就显得格外迫切和重要。 几年来灌水镇经营拖拉机的营机户总是在50户左右。这些营机户为尽快掌握现代科 相似文献
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今年,农七师130团农机户投资1000万元用于农机新技术引进和拖拉机更新。10月3日,由该团场农机户个人投资380.38万元,购置的“铁牛”724型拖拉机16台,铁牛1204型拖拉机10台和东方红1002型拖拉机已全部到位。 相似文献
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Overland water and salt flows in a set of rice paddies 总被引:1,自引:0,他引:1
E. Playn O. Prez-Coveta A. Martínez-Cob J. Herrero P. García-Navarro B. Latorre P. Brufau J. Garcs 《Agricultural Water Management》2008,95(6):645-658
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. 相似文献
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车用发动机润滑油失效规律与更换周期研究 总被引:7,自引:0,他引:7
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。 相似文献
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赵国杰 《农业机械化与电气化》2011,(4):106-107
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。 相似文献
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苑庆刚 《农业机械化与电气化》2010,(3):52-54
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。 相似文献
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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。 相似文献
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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。 相似文献
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对《种子法》存在问题的探讨 总被引:1,自引:0,他引:1
李鹏 《农业机械化与电气化》2011,(6):129-130
《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。 相似文献
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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. 相似文献
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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。 相似文献