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运行机构是温室大棚输送器的主要组成部分。阐述温室大棚输送器运行机构的结构设计思路,详细介绍运行机构中车轮、轨道、电动机、制动器、减速机构的设计方法,以期为温室大棚输送器的设计及性能改进提供技术参考。 相似文献
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针对温室内物料运送难的问题,研制一种简便的大棚多功能输送器.介绍多功能输送器关键部件的设计思路及安装方法,总结机具的主要技术经济参数及特点,展望其推广应用前景,为推进全省设施农业发展提供技术支持. 相似文献
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温室大棚灌溉技术的探讨 总被引:4,自引:0,他引:4
分析了温室大棚蔬菜生产时对湿度的要求,提出了温室大棚内的空气湿度的调控方法,对比了温室大棚的几种灌溉方法.重点对温室大棚微灌技术作出分析,讨论了温室大棚膜下滴灌、重力滴灌、渗水灌溉技术,并且提出温室大棚利用雨水资源的方法以及灌水器堵塞的防治方法. 相似文献
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SL350型番茄收获机的引进与试验 总被引:4,自引:1,他引:3
天业集团于1999年8月引进美国FMC公司生产的SL350型番茄收获机,并对40hm2番茄进行收获试验。1主要结构及工作原理SL350型番茄收获机由往复式切割器、倾斜输送器、番茄与茎叶输送装置及分离装置、色选装置、成熟番茄输送装置、发动机、行走装置、液压系统、电控装置和驾驶室等组成。如图所示SL350型番茄收获机结构简图1.往复切割器2.液压传动装置3.驾驶室4.倾斜输送器5.番茄与茎叶分离装置6.茎叶输送装置7.发动机8.行走装置9.成熟及未成熟番茄输送装置10.色选装置11.成熟番茄输送装置12.踏板工作时,往复式切割器将番茄茎杆切断,由倾斜… 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