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Precision planting is one key point of precision agriculture.A doorframe type swing seedling pick-up device for the automatic precise field transplanter was designed and tested in a laboratory.The seedling device could automatically extract seedlings from growing trays, transfer them, and release them into the planting unit where they were to be precisely transplanted into the ground.It consisted of a path manipulator and two grippers.The path manipulator for seedling extraction was constructed with creative design of Ⅱ-type mechanism combination in series.It consisted of an oscillating guide linkage mechanism and a grooved globoidal cam mechanism.According to the planned seedling pick-up trajectory, the design of the path manipulator for seedling extraction was finished with a set of the closed loop vector equation.The gripper was a pincette-type mechanism using the pick-up pins to penetrate into the root mass for seedling extraction.It consisted of multiple pick-up pins, U-type pull rod, shaft, stop block, compression spring and frame.The mechanical dimensions of the gripper were determined by the tray size and plant characteristic with a set of rectangular equations and the boundary constraint conditions.The final gripper was developed on the basis of cultural practice for vegetable seedling in China.A prototype of the seedling pick-up device was constructed to examine whether its working efficacy was satisfactory or not.According to the analysis on the work process, the seedling pick-up device could precisely complete a work cycle of approaching, penetrating, extracting, transferring, erecting and discharging a seedling.Taking pepper seedlings, tomato seedlings and cucumber seedlings as the transplanting objects, the performance tests were conducted to evaluate the practicality and adaptability of the pick-up device.The laboratory evaluation showed that the pick-up device equipped with two grippers could extract 70 seedlings per minute with an average success ratio of 90.49%.The quality of extracting seedlings was satisfactory. 相似文献
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温室穴盘苗自动移栽机设计与试验 总被引:12,自引:0,他引:12
针对种苗从高密度穴盘移植到低密度穴盘,或者从穴盘直接移植到花盆的温室穴盘苗移栽生产需要,设计了一种轻简型自动移栽机。利用成熟的直线模组和无杆气缸组合设计出自动移栽机械臂,驱动取苗末端执行器往复于来源盘和目标盘进行取苗、移苗、栽苗操作,采用双排链传动实现穴盘和花盆输送,对穴盘苗的夹取操作采用气动两指四针钳夹式夹钵取苗方法。根据所设计的移栽机工作要求,构建电气控制系统。试制样机,开展试验研究。采用直线位移传感器系统检测分析机器取苗移栽移位性能,结果显示对于128/72孔穴盘苗,移栽效率分别达到1 221株/h和1 025株/h,运用单样本t检验法分析得到实测取苗移位间隔与理论设定穴孔间隔无显著差别,标准差低于0.5,整机工作精度准确。以当地自行培育的种苗为移栽对象,进行温室穴盘苗移栽生产试验,对比分析自动取苗移栽效能,结果显示多种穴盘苗移栽成功率平均达到90.70%,苗钵夹取破碎率低于5%,自动取苗移栽效果较好。 相似文献
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高职院校化学教学多采用传统的教学方法,即教师讲述理论知识占主导地位,而实验作为这门学科的灵魂,却只能作为一种辅助教学的手段,这种教学方法势必会降低教学的效果。多媒体模拟化学实验作为现代化科学技术的产物,被逐步应用到化学教学过程中,这种教学方法突破了实验条件的制约,突破了时间和空间的局限性,使化学实验更好地、更形象地、更直观地展示在学生面前,激发了学生自主学习的积极性,同时它也体现了绿色化学零污染、零排放的绿色理念,体现了教育现代化、科学化,大大提高了教师的教和学生的学的效率。 相似文献
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食品安全检测要求及时、准确地检测出食品中的病原微生物。近年来,随着各种病原微生物检测方法的出现和发展,分子生物学检测技术因其特异性和灵敏性而受到广泛的关注。主要介绍了PCR技术、基因探针检测方法和基因芯片技术的原理。在食品微生物检测中的应用和发展方向及前景。 相似文献
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银杏(Ginkgo Biloba L.)是一种具有活化石之称的古代二叠纪子遗树种,由于其果、叶、皮等有很高的保健和药用价值,深受国内外学者和企业家的青睐. 相似文献
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化学发光分析法(chemiluminescenceanalysis,CL)具有灵敏度高、线性范围宽、仪器设备简单等优点.流动注射分析法(flow injection analysis,FI)是指在热力学非平衡条件下,在液流中重现处理试样或试剂区带的定量流动分析技术.将CL与FI相结合而形成的FI-CI分析法具有分析速度快、精度高、易于实现自动化等特点,其研究和应用越来越广泛. 相似文献
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试验旨在探究不同化学方法处理的高粱秸秆对肉牛的生长性能、养分表观消化率及血清生化指标的影响。选取体重相近、健康的育成牛35头,随机分为5组,每组7个重复,每个重复1头牛。A组(对照组)肉牛饲喂未经特殊处理的高粱秸秆,B组、C组、D组肉牛分别饲喂经“三化”处理、碱化复合处理、氨化处理的高粱秸秆,E组肉牛饲喂含有苜蓿的日粮。结果表明,B组、D组肉牛平均日增重分别比A组提高了12.36%、6.74%(P<0.05),B组、C组肉牛平均日采食量显著高于A组(P<0.05)。C组、D组肉牛粗蛋白表观消化率显著高于A组(P<0.05),酸性洗涤纤维表观消化率显著降低(P<0.05),各处理组肉牛中性洗涤纤维表观消化率均显著低于A组(P<0.05)。B组、C组、D组肉牛瘤胃氨态氮含量显著高于A组(P<0.05),C组、D组肉牛瘤胃总挥发性脂肪酸含量显著高于A组(P<0.05),B组、C组、D组肉牛瘤胃微生物含量比A组分别提高16.00%、27.58%、28.68%(P<0.05)。各处理组肉牛血清尿素氮含量显著高于A组(P<0.05)。研究表明,... 相似文献
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分析化学是一门理论性高、实践性强、应用性广的课程。切实有效的化学教学可以使学生更好地理解和掌握理论教学的内容,使学生了解和使用现代仪器设备、信息工具与手段,养成认真细致、求实求精、有条不紊的学习习惯和做事态度。参与实践活动可以培养学生观察、分析和解决问题的能力,激发其学习兴趣、好奇心和创造欲望。 相似文献