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为提高肥料的利用率,开发设计一种开沟合垄深施肥耕耙犁.介绍机具的主要结构组成和工作原理,探讨传动系统、碎土器和工作部件的选型和设计思路,为肥料深施作业提供性能可靠的实用机具. 相似文献
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张家港市水稻机插施肥一体化技术试验 总被引:1,自引:0,他引:1
《农业装备技术》2015,(5)
<正>水稻机插、施肥一体化技术是一种与机插秧作业配套的机械化施肥技术,主要用于水稻的基肥撒施作业。该技术可在机插秧作业的同时将颗粒状的缓释肥(或复合肥)精确、均匀的施入秧苗侧部一定深度的泥中,使肥料在泥中慢慢分解,延长肥效,提高肥料利用率,减少肥料的流失,促进水稻根系对肥料的吸收,降低过量施肥对土壤、空气、水源所造成的污染,同时减轻种植户的劳动强度和作业成本。本次试验选用已经成熟的插秧、施肥一体机,开 相似文献
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水稻机插秧同步侧深施肥技术是在水稻机插秧作业时,通过侧深施肥装置将肥料按照农艺要求精确定量的施用在苗侧靠近根部泥浆中,并由浮船刮板覆土,实现秧苗根系对肥力的精准吸收,避免肥料随水流漂移,具有显著的提高肥料利用率、促进水稻生长、缩短秧苗返青时间、降低成本等优势,实现减肥不减产的目的,对农业的可持续发展具有其重要意义。 相似文献
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水肥一体化施用技术要点 总被引:1,自引:0,他引:1
水是人类赖以生存的自然资源,更是生物赖以生存的基本条件,没有水就没有生命.肥料是作物的"粮食",合理施肥是农作物高产优质的基础.
水肥一体化技术是将灌溉与施肥有机结合的一项农业新技术,主要是借助新型微灌系统,根据土壤养分含量和作物的需水、需肥规律,在灌溉的同时将可溶性固体肥料或液体肥料配兑成肥液,与灌溉水一起均匀、准确地输送到作物根部土壤中,供给作物吸收,并且精确控制灌水量、施肥量、灌溉次数和施肥时间,达到"以水调肥"和"以肥促水"的水肥耦合技术.由于灌溉过程主要是根部灌溉,肥料也随水直接被输送到根系的周围,直接被作物吸收利用,极大地减少灌溉和肥料的投入,提高水资源和肥料的利用率,并显著地提高作物产量和品质. 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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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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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