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设施农业可调光质精确补光系统 总被引：4，自引：0，他引：4
针对环境温度、光质和光强对农作物光合作用的影响,提出结合实时环境检测、特定波段补光与定量决策的精确补光方法,设计了基于反馈控制机制的定量决策算法。以单片机为核心控制器件,设计了可调光质的精准补光系统,可根据温度及红蓝光目标光强与实时光强的差值精确计算补光量,通过PWM占空比调整LED输出光强。实验结果证明系统可实现按需补光;采用的LED光源较白炽灯节能54%,较荧光灯节能83%;在相同LED光源时,较常规LED补光系统的节能率在不同光质阈值和气候条件下具有一定波动,平均节能在30%以上。 相似文献
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以毛蟹品种乌龙茶净毛茶为材料,采用三段式烘焙,设置105℃/120min,120℃/90min,135℃/60min三个试验条件水平,并以烘焙的第一、二、三阶段为因素进行正交试验设计,探索不同烘焙方式对毛蟹乌龙茶的感官品质和生化成分的影响。正交实验结果表明,三段式烘焙的各阶段(的烘焙温度和时间)对茶样中水浸出物、茶多酚、茶氨酸、咖啡碱等生化成分含量变化的影响大小顺序分别为:第一阶段(A)第二阶段(B)第三阶段(C),其中第一阶段和第二阶段对水浸出物含量和茶氨酸含量的影响显著,第三阶段的影响未达显著水平。此外,烘焙后茶样的各生化成分含量随各处理间整体烘焙温度的提升而呈明显的下降趋势。感官审评结果表明,处理6(120℃/90min、135℃/60min、120℃/90min)茶样的感官审评总分最高,且中高温烘焙对改善毛蟹品种乌龙茶感官品质的效果较好。 相似文献
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《现代农业装备》2018,(5)
为研究不同光质对台湾金线莲(Anoectochilus formosanus Hayata)的生长和品质的影响,在温度和光环境可控的植物工厂中利用光谱组合LED光源配置5种光质:红光(R)、蓝光(B)、红蓝光1∶1(R1B1)、红蓝光1∶2(R1B2)和白光(CK)对台湾金线莲进行60 d光照试验。试验结果表明,不同的光质处理对金线莲的株高、茎直径、叶面积、生物量和有效成分积累量产生显著差异,其中,蓝光处理显著降低株高和叶面积的增长;红光处理显著抑制茎秆直径的增长;红蓝光1∶1、红蓝光1∶2两种复色光处理均显著降低株高、鲜重和总黄酮积累量;白光处理下的总体长势、可溶性糖和总黄酮积累量比红光、蓝光、红蓝光1∶1、红蓝光1∶2处理的效果更佳,是台湾金线莲在此栽培阶段的最适光质,为金线莲的人工光照栽培提供参考。 相似文献
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基于单片机的温室大棚LED智能补光系统设计 总被引：1，自引：0，他引：1
《中国农机化学报》2016,(10)
目前,在黑龙江地区的温室大棚内种植反季节或当下蔬菜时,补光时间和补光强度全部靠人员经验,因此无法达到精准控制。本文针对这一问题设计一个基于AVR单片机的温室大棚LED智能补光系统。该系统基于ATmega16L单片机,利用光敏电阻阻值变化引起电路电流的变化,测出大棚内光照的强度,设定占空比进行间断补光,通过脉宽调制(PWM)控制LED灯光照强度,从而达到实际需要的光饱和点。本文选用蓝光、红光比例1∶8的LED补光灯补光,代替传统的一些补光手段。该系统节能环保、安全性高、稳定性好,在温室大棚智能控制方面具有很好的应用和推广前景。 相似文献
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在温室条件下,以荧光灯为对照,以LED灯板为人工光源,探究红蓝光质对水培盆栽绿叶生菜和紫叶生菜生长和光合色素含量的影响,以期为植物工厂条件下生产不同叶色蔬菜提供光环境参数。结果表明,绿叶生菜和紫叶生菜光合色素含量在RB 2∶1（RBⅠ）处理下显著高于对照和其他处理,且随蓝光比例下降而减少,在RB 1∶2（RB Ⅲ）和荧光灯（F）处理下含量最低。且绿叶生菜光合色素含量对红蓝光比例的变化敏感程度低于紫叶生菜。绿叶生菜地上部分鲜质量、根系鲜质量和地上部分干质量均以RB 1∶1（RB Ⅱ）处理最大。紫叶生菜地上部分鲜质量在白光（W）对照处理下最大,根系鲜质量和根系干质量在RB 2∶1（RBⅠ）光照下最高,地上部分干质量则在不同光质变化下没有显著差异。绿叶生菜和紫叶生菜分别以RB 1∶1（RB Ⅱ）和白光（W）光质照射培养最佳。 相似文献
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在温室条件下,以荧光灯为对照,以LED灯板为人工光源,探究红蓝光质对水培盆栽绿叶生菜和紫叶生菜生长和光合色素含量的影响,以期为植物工厂条件下生产不同叶色蔬菜提供光环境参数。结果表明,绿叶生菜和紫叶生菜光合色素含量在RB 2∶1(RBⅠ)处理下显著高于对照和其他处理,且随蓝光比例下降而减少,在RB 1∶2(RBⅢ)和荧光灯(F)处理下含量最低。且绿叶生菜光合色素含量对红蓝光比例的变化敏感程度低于紫叶生菜。绿叶生菜地上部分鲜质量、根系鲜质量和地上部分干质量均以RB 1∶1(RBⅡ)处理最大。紫叶生菜地上部分鲜质量在白光(W)对照处理下最大,根系鲜质量和根系干质量在RB 2∶1(RBⅠ)光照下最高,地上部分干质量则在不同光质变化下没有显著差异。绿叶生菜和紫叶生菜分别以RB 1∶1(RBⅡ)和白光(W)光质照射培养最佳。 相似文献
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在设施水培条件下,以黄金四季奶油小白菜为试验材料,LED灯为人工光源,自然光为对照,研究不同光谱LED植物光灯的红蓝光波段组合对黄金四季奶油小白菜生长参数的影响,为植物工厂水培小白菜提供人工补光数据支撑。试验设定为蓝光(455nm)相对光谱固定不变,红光相对光谱分别为T1(7.53%)、T2(15.40%)、T3(30.28%)条件下的生长速度及品质。结果表明,红光相对光谱为30.28%时试验组小白菜的菜叶长度、株高、蛋白质以及叶绿素含量均显著高于其他处理,30.28%的红光相对光谱可作为水培小白菜的适宜光配合。 相似文献
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夜间补光对黄瓜幼苗形态的调节与补光方式的确定 总被引：1，自引：0，他引：1
为确定光质夜间延时补光对不同生长阶段黄瓜幼苗形态的影响,制定黄瓜育苗夜间延时补光模式,对LED夜间延时补光对黄瓜幼苗形态发育的影响进行了试验研究。选取"津春四号"黄瓜为试材,以下胚轴长、子叶面积、茎粗、叶面积、节长、干物质量、叶绿素含量以及壮苗指数为指标,研究使用红光(R,630 nm)和红蓝混合光(RB,630 nm∶660 nm=8∶2)两种LED光源夜间延时补光4 h对不同生长阶段黄瓜幼苗形态的影响,利用Logistic曲线对叶面积增长速率进行拟合。结果表明:子叶期红光延时补光幼苗子叶面积和茎粗最大,分别比对照组提高了61.60%和19.55%;一叶期红光延时补光幼苗叶面积和茎粗最大,分别比对照组提高了25.11%和14.72%;成苗期红蓝光延时补光幼苗叶面积、茎粗、干物质量、叶绿素含量和壮苗指数最大,分别比对照组提高了41.92%、17.75%、45.45%、21.92%、200.00%。利用红光夜间延时补光能够促进前期(子叶期和一叶期)黄瓜幼苗的生长,红蓝混合光夜间延时补光可促进后期(二叶期至成苗期)黄瓜幼苗的生长、提高幼苗壮苗指数。 相似文献
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Overland water and salt flows in a set of rice paddies 总被引：1，自引：0，他引：1
E. Playn O. Prez-Coveta A. Martínez-Cob J. Herrero P. García-Navarro B. Latorre P. Brufau J. Garcs 《Agricultural Water Management》2008,95(6):645-658
Cultivation of paddy rice in semiarid areas of the world faces problems related to water scarcity. This paper aims at characterizing water use in a set of paddies located in the central Ebro basin of Spain using experimentation and computer simulation. A commercial field with six interconnected paddies, with a total area of 5.31 ha, was instrumented to measure discharge and water quality at the inflow and at the runoff outlet. The soil was classified as a Typic Calcixerept, and was characterized by a mild salinity (2.5 dS m−1) and an infiltration rate of 5.8 mm day−1. The evolution of flow depth at all paddies was recorded. Data from the 2002 rice-growing season was elaborated using a mass balance approach to estimate the infiltration rate and the evolution of discharge between paddies. Seasonal crop evapotranspiration, estimated with the surface renewal method, was 731 mm (5.1 mm day−1), very similar to that of other summer cereals grown in the area, like corn. The irrigation input was 1874 mm, deep percolation was 830 mm and surface runoff was 372 mm. Irrigation efficiency was estimated as 41%. The quality of surface runoff water was slightly degraded due to evapoconcentration and to the contact with the soil. During the period 2001–2003, the electrical conductivity of surface runoff water was 54% higher than that of irrigation water. However, the runoff water was suitable for irrigation. A mechanistic mass balance model of inter-paddy water flow permitted to conclude that improvements in irrigation efficiency cannot be easily obtained in the experimental conditions. Since deep percolation losses more than double surface runoff losses, a reduction in irrigation discharge would not have much room for efficiency improvement. Simulations also showed that rice irrigation performance was not negatively affected by the fluctuating inflow hydrograph. These hydrographs are typical of turnouts located at the tail end of tertiary irrigation ditches. In fact, these are the sites where rice has been historically cultivated in the study area, since local soils are often saline-sodic and can only grow paddy rice taking advantage of the low salinity of the irrigation water. The low infiltration rate characteristic of these saline-sodic soils (an experimental value of 3.2 mm day−1 was obtained) combined with a reduced irrigation discharge resulted in a simulated irrigation efficiency of 60%. Paddy rice irrigation efficiency can attain reasonable values in the local saline-sodic soils, where the infiltration rate is clearly smaller than the average daily rice evapotranspiration. 相似文献
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瓦房店市是我国重要的水果生产基地,在国内水果生产领域占有重要地位。随着水果市场化的不断深入,如何满足和适应国内外市场需求成为瓦房店市水果生产的关键问题。从瓦房店市水果生产实际出发,阐述了实施水果生产标准化的必要性,提出了发展水果生产标准化的具体措施。 相似文献
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对引进的谷子新品种金谷子耐旱TG118进行品种比较试验和多点试种。结果表明：该品种抗旱、耐瘠、适应性强,稳产、高产、抗病抗风抗倒伏强,品质优良,粮草兼用,种植简单,省工易管;一般产量在6000kg/hm2以上,比当地主栽品种增产20%以上。最高产量达9450kg/hm2,适于在辽西北地区推广应用。 相似文献
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对《种子法》存在问题的探讨 总被引：1，自引：0，他引：1
李鹏 《农业机械化与电气化》2011,(6):129-130
《种子法》是我国种植业第一部法律。自实施以来,为依法加强种子管理提供了有力的法律支撑,促进我国种子产业发生翻天覆地的变化。但随着依法管理工作的深入和种子产业的快速发展,《种子法》及配套规章的一些问题逐步显现出来。对《种子法》及配套规章存在的问题进行深入分析,对需要进一步补充的章节以及需要调整的内容进行深入探讨,以求更加完善和明确。 相似文献
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About 30 years have passed since the Government of Egypt embarked on implementing a series of large scale drainage projects. At present, about 3.8 million acres have been provided with drainage systems on the basis of systematic pre-drainage investigations and designs. The target is to provide drains in approximately 6.4 million acres in the Nile Valley and Delta.The implementation of the subsurface drainage system is carried out by the public sector and private contractors under direct supervision of governmental regional departments. The implementation process depends on many factors related to the drainage material, machinery, manpower, site requirements, farmers and organizations involved. Problems and constraints are sometimes challenging, however, the annual rate of implementation has gradually increased to 170,000 acre/year.This paper discusses the different aspects involved in the implementation process of drainage systems. The development in materials, machinery and construction technologies will be reviewed. Institutional and management factors are going to be also considered. 相似文献
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在新世纪,面对机遇和挑战,党的十六大把“社会更加和谐”作为全面建设更高水平的小康社会的一个重要目标。中国人素有社会和谐的理想;西方人自古也向往社会和谐;借鉴东西方两种和谐社会思想的经验、教训,构建社会主义和谐社会理论。 相似文献
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Gunter Wriedt Marijn van der Velde Alberto Aloe Fayçal Bouraoui 《Agricultural Water Management》2009,96(5):771-789
We present a pan-European irrigation map based on regional European statistics, a European land use map and a global irrigation map. The map provides spatial information on the distribution of irrigated areas per crop type which allows determining irrigated areas at the level of spatial modelling units. The map is a requirement for a European scale assessment of the impacts of irrigated agriculture on water resources based on spatially distributed modelling of crop growth and water balance. The irrigation map was compiled in a two step procedure. First, irrigated areas were distributed to potentially irrigated crops at a regional level (European statistical regions NUTS3), combining Farm Structure Survey (FSS) data on irrigated area, crop-specific irrigated area for crops whenever available, and total crop area. Second, crop-specific irrigated area was distributed within each statistical region based on the crop distribution given in our land use map. A global map of irrigated areas with a 5′ resolution was used to further constrain the distribution within each NUTS3 based on the density of irrigated areas. The constrained distribution of irrigated areas as taken from statistics to a high resolution dataset enables us to estimate irrigated areas for various spatial entities, including administrative, natural and artificial units, providing a reasonable input scenario for large-scale distributed modelling applications. The dataset bridges a gap between global datasets and detailed regional data on the distribution of irrigated areas and provides information for various assessments and modelling applications. 相似文献
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在介绍粉质仪和拉伸仪结构和原理的基础上,探讨了粉质曲线中吸水率、形成时间、稳定时间、弱化度和评价值等指标与面粉品质的关系,以及如何根据拉伸曲线中面团最大拉伸阻力、延伸度和拉伸曲线面积等指标来评价面团品质,并结合生产实际,概述了粉质仪和拉伸仪在面粉生产中的作用。 相似文献
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车辆ABS控制算法的研究及探讨 总被引：1，自引：0，他引：1
对现代汽车的ABS控制算法作了一些简单的介绍,同时指出了它们的一些缺陷,相应地提出了几种对ABS的其它控制方法并加以探讨,其中着重论述了ABS门限值控制算法中参考车速的确定方法和基于附着系数的控制算法。 相似文献