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刘明伟 《农业机械化与电气化》2010,(2):60-61,64
物理农业实用技术的应用是发展生态农业的有效途径之一。通过与传统化学农业相比,阐述发展物理农业技术的意义和优势。结合鞍山市生产实际,介绍4种物理农业实用技术的应用原理及其成效,并对未来物理农业实用技术的发展前景进行展望。 相似文献
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农机推广是农业技术推广的组成部分,是发展农业机械化、振兴农业、实现农业现代化的重要措施,是将科技成果和实用技术普及应用于农业生产过程的重要环节. 相似文献
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近年来天津市西青区农业加快发展,农业结构调整取得显著成效,农业产业化建设取得突破性进展,循环生态农业建设全面启动,全区农业由粗放型逐步向集约型转变。物理农业工程技术在天津市西青区现代化农业发展中发挥着重要的作用。介绍了物理农业的基本概念、优势以及其在天津市西青区的实际应用,指出了物理农业在应用中存在的问题及未来发展的方向。 相似文献
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孙亚文 《农业机械化与电气化》2011,(8):63-64
介绍应用物理农业技术的原理,通过物理农业技术在蔬菜大棚中的应用试验,证实应用物理农业技术可促进蔬菜的长势、减少病虫害发生、提高产量和品质,从而实现蔬菜生产向无农药、无化肥的经济、绿色、环保方向发展。 相似文献
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物理农业技术在温室大棚蔬菜生产中的应用 总被引:2,自引:0,他引:2
介绍应用物理农业技术的原理,通过物理农业技术在蔬菜大棚中的应用试验,证实应用物理农业技术可促进蔬菜的长势、减少病虫害发生、提高产量和品质,从而实现蔬菜生产向无农药、无化肥的经济、绿色、环保方向发展。 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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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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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