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南方冬种马铃薯收获机的应用现状与研究展望 总被引:1,自引:0,他引:1
实现南方冬种马铃薯机械化收获对推进马铃薯主粮化进程、扩大南方冬种马铃薯种植面积具有重要意义。现有马铃薯收获机在应用过程中存在挖掘阻力大、易壅堵、明薯率低、伤薯率高等问题,导致目前南方冬种马铃薯收获以人工或畜力为主,机械化应用水平低。为此,从南方冬种马铃薯种植模式和种植环境出发,在分析现有马铃薯收获装置挖掘部件和分离部件的基础上,对南方冬种马铃薯收获机的进一步研究做出了展望,提出一种双重振动减阻挖掘部件、一种可分离薯、土、膜的振动杆条升运链分离部件,以及一种可分离薯、土、草的拨杆抖动筛分部件,旨在为南方冬种马铃薯地膜覆盖栽培模式及稻草覆盖栽培模式下机械化收获装置的研制提供参考。 相似文献
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近年来全球对中药材的需求日益旺盛,中药材种植面积逐年增加,根茎类中药材收获机的需求也随之增长。目前我国根茎类中药材收获仍以人工收获和中小型挖掘机收获方式为主,机械化水平较低、生产效率低,严重制约中药材产业的发展。从我国中药材种植现状出发,综合分析我国根茎类中药材收获机械化应用和研究现状,重点阐述关键部件挖掘机构、分离机构和输送机构的研究现状,总结归纳制约收获机械化发展的主要问题:农机农艺融合程度不足、联合收获机械的研发积极性不高、收净率和破损率缺乏系统性研究以及收获作业的智能调控技术缺乏研究。提出低耗深挖技术、柔性低损分离输送技术和智能调控技术是我国根茎类中药材收获机械化的未来发展趋势,为我国根茎类中药材收获机的研究提供借鉴和参考,以促进根茎类中药材收获机械化进一步发展。 相似文献
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我国是马铃薯生产大国,种植面积与总产量均居世界首位,但国际竞争力较弱,机械化生产水平尤其是机收率低严重制约马铃薯产业化的发展。介绍了国内外马铃薯收获机械发展现状,指出我国马铃薯收获机械存在的问题,并对未来发展趋势进行展望。 相似文献
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目前,我国马铃薯全程机械化生产的水平还很低,特别是马铃薯机械化收获这一环节,据不完全统计,国内马铃薯机械化收获率不足5%。不仅如此,马铃薯机械化方面的教科书还少之又少,特别是学术水平较高的专著。刘汉武等编著的《马铃薯全程机械化生产技术》 相似文献
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The fractional outflow rate of water from the rumen, measured as the rate of disappearance of the chromium complex of ethylenediamine tetra-acetic acid, was related to a number of dietary factors. A multiple regression equation was derived which expressed fractional outflow rate as a function of the intakes of dry matter, ash, acid-detergent fibre and crude protein.The data analysed consisted of 243 observations for sheep on 59 diets, including forage, concentrate and mixed diets. The ranges covered by the data were: fractional outflow rate 0.7–3.6 day?1; dry matter intake 560–1400g/day; ash 4–30%, acid-detergent fibre 7–41%, crude protein 5–26 % of dry matter; there were no observations for sheep of less than 34 kg liveweight.The equation accounted for 56·3 % of the total variance. Between-sheep variance could not be calculated for the whole of the data but was undoubtedly substantial since, for a sixth of the data, it was known to account for 38 % of the total variance. 相似文献
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《Journal of Agricultural Engineering Research》1998,69(3):249-254
A model to represent the discolouration of dried powder of carrots as a function of temperature was developed. Two types of carrots, Asian and European, containing large amount of lycopene and β-carotene, respectively, were tested. The dried powder was stored under an atmosphere with O2and at three different temperatures, 5,20 and 35°C. The surface colour of the powder was monitored during storage by a Hunter colour ratioa/b. In the proposed model, the rate of oxidation was assumed to be represented by the product of the fraction of concentration of oxidized pigment at arbitrary time and a specific rate of oxidation of pigment. The rate parameters in the proposed model were calculated by fitting the experimental data with smooth curves by trial and error at the end of the induction period but before discolouration took place. The frequency constant and activation energy, expressing the temperature dependence of the rate parameters, were expressed by the Arrhenius relation. The simulation results of a Hunter colour ratioa/bof dried powder at 25°C showed good agreement with the experimental data, suggesting that the proposed model was effective for the prediction of discolouration of dried powder of both types of carrot. The use of the induction period in the manner described may enable the shelf life of dried powder to be predicted. 相似文献
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感官检验棉花的品级,这是农村常见的一种检测手段.它的一个主要特点就是存在不确定性.这是由于检验员的品级检验水平存在一定的差异,其中有很多因素制约着检验的结果.文章对影响感官检验结果的因素进行了系统的分析. 相似文献
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从灾害经济学的角度探讨了城镇供水优化调度的必要性和可能性,认为在缺水不可避免的情况下,对供水进行优化调度可以减小缺水带来的损失,产生较好的减灾效益,特别是可以大大减小严重干旱的灾害效应。并根据水资源的特性,提出了缺水损失的计算模式以及优化调度的原则和方法。 相似文献