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由原水电部科技司、河南省水利厅、中国科学院农田灌溉研究所承担建设的河南省偃师县山化乡关窑村千亩滴灌工程,1980年5月由原水电部科技司组织通过验收交付使用。整个工程包括提水蓄水自压半固定式滴灌914亩,机组式移动滴灌224亩.主要滴灌大田作物小麦、玉米,建试点皎目,的是通过较大面积的试点工作和开展滴灌技术研究明确以下几个问题: 1,研究干旱缺水地区粮食作物滴灌的效果; 2.探索大面积粮食作物特别是对密 相似文献
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<正> 提蓄滴灌溉工程位于河南省偃师县山化乡关窑村,地处豫西邙山岭上,是历史上严重干旱缺水地区,人畜用水相当困难,农作物产量低而不稳。1979年11月建成两个自压半固定式滴灌系统,控制面积914亩;五部移动滴灌机组,控制面积250亩。1980年5月水电部委托河南省水利厅组织鉴定,验收合格正式交付地方使用。该系统主要是滴灌大田作物小麦、玉米和棉花等。 相似文献
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烟叶滴灌增产效果的研究 总被引:3,自引:0,他引:3
张贵轩 《中国农村水利水电》2001,(4):19-20
为了研究烟叶滴灌的增产效果,选择滴灌与不灌两个处理做对比试验。在介绍试验区自然条件和滴灌系统布置试验方法的基础上,叙述了滴灌的用水量、滴灌对土壤水分的影响、滴灌对烟叶质量和产量、效益等的影响。 相似文献
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介绍了一种适合小农户的首部移动式滴灌机的试验过程及结论.通过对两种滴灌机在柴油机大、中、小油门状况下,不同压力状况下的流量及耗油量数据记录分析.从两种滴灌机的压力-油耗关系曲线,压力-流量关系曲线分析得出结果,在3种油门状况下,两种滴灌机耗油量都随着压力的增加而增加,流量随着压力的增加而减小;从不同油门的两种滴灌机油耗柱状图、流量柱状图得出结果,两种滴灌机在中油门状态下均具有能耗低、流量大、操作的稳定性和可靠性好的特点,而且Ⅱ型滴灌机在柴油机功率大于Ⅰ型滴灌机的情况下反而耗油量小,流量也大大增加.最终确定Ⅱ型滴灌机在流量油耗两方面的指标上都优于Ⅰ型滴灌机,Ⅱ型滴灌机确定为低能耗高效率的动力系统. 相似文献
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一、滴灌技术在我县农业生产中的地位水是人类赖以生存的基础,而大自然赋于遵化的可利用水资源并不足。多年平均水资源量3.3亿米~3,而且降水量在时空分配上,无论年际、年内,还是南北三山、中部两川都不均匀。近年来由于工农业的发展和人口增加,需水量与日俱增,年工农业和生 相似文献
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一、千亩滴灌试点的基本情况滴灌试点是在河南省洛阳地区偃师县山化公社的关瑶大队。由于岭高水低,年降雨量少,历来是个干旱缺水的地方,人畜吃水也有困难。农业生产低而不稳,基本上靠天吃饭。 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