农机用O形密封圈滚子链的耐磨性能

农机用O形密封圈滚子链的台架和道路的对比试验研究表明，铰链磨擦副的润滑状态改善后，其耐磨性能大幅度提高，磨损寿命远高于普通农机滚子链。同时还研究了O形圈链条与普通链条的磨损机制，并微观分析了磨损表面形貌，指出O形圈链条的磨损形式是以疲劳磨损为主，而普通链条因试验工况不同其主要磨损形式有所改变。     

实验室制粒机

实验室制粒机主要为大专院校、科研单位,在实验室内压制各种规格的颗粒饲料,作饲养试验用。制粒机的研制试验结果表明,各项性能指标和制造质量均已达到设计要求,而在其使用的方便性和配套性方面超出了进口样机。     

气吸辊式水稻精量直播排种器的设计与试验研究

针对我国现有水稻精量直播排种器对种子适应性差、伤种率高、排种速度低等问题,设计气吸辊式水稻精量直播排种器,并进行种子吸附条件分析,确定影响工作性能的参数;完成了参数的单因素试验和正交试验研究。结果表明:所设计的排种器能够满足水稻芽种的精量穴播和低伤芽率的要求;吸种针孔径与排种器吸种性能影响呈正相关趋势,吸种针孔径选择应大于0.60mm;影响排种器播种性能的因素主次顺序依次为吸种针孔径、吸种真空度、吸种辊转速,当吸种针孔径为1.55mm、吸种真空度为0.035MPa、吸种辊转速为50r/min时播种效果较好,吸种合格率为98%。     

滚杠式红枣分级机的试验方法

总结了测试红枣分级机性能的试验方法,以期为方便准确地测试红枣分级机的各项性能提供参考。     

Necessity of shading on north facade and optimal selection of shading device

This research is aimed at exploring the necessity of shade on the north facade and optimal selection of shading device. Firstly, the direct and diffuse solar radiation distribution on the surface of each orientation is analyzed in the air conditioning period in Shanghai and Xiamen. Secondly, the simulated building model is established to analysis the impact of different external shades on solar radiation heat gain and day-lighting with Energy-plus. These shades include fixed overhang of different dimensions, roller with different properties and louver of different slat angles. The glare index of different shade devices is also analyzed, results show that the hours exceeding the glare index set point of the fixed overhang and roller are far more than louver’s. Finally, the impact of different external shades on lighting energy consumption and air conditioning energy consumption on the north facades is analyzed. Results show that the use of medium-reflect and medium-transmit external roller is the most energy-saving in Shanghai, the effect of adjustable external blind is close to the roller, and the effect of fixed overhang is not obvious. In Xiamen, the use of adjustable external blind is the most energy-saving, the next is roller, and the last is fixed overhang. Taking energy-saving and glare into consideration, adjustable louver is the best choice of shade on the north facade in Shanghai and Xiamen.     

Heritable characters of the red blood cells of sheep

Extract

From the start I want to make it clear that the research work described here is the work of one of us (J.V.E.), and the reason why I am presenting his work is that Evans comes from New Zealand and presented a paper on this subject to the annual meeting of the British Association for the Advancement of Science last September in Sheffield, so that it seemed appropriate that his work should also be presented to this Society.     

30％茚虫威悬浮剂防治水稻稻纵卷叶螟的效果

应用30％茚虫威悬浮剂防治水稻稻纵卷叶螟(Cnaphalocrocis medinalis Guene).试验结果表明,该药剂对稻纵卷叶螟具有良好的防治效果,施药量在18、27、36 g(ai)/hm2浓度时,药后18d防治效果分别为82.08％、84.28％、87.68％,且持效期较长.试验期间未发现该药剂在供试剂量下对水稻产生药害,从使用成本与防治效果两方面综合考虑,生产上30％茚虫威悬浮剂的使用剂量以27～36 g(ai)/hm2为宜.     

番茄育苗播种机双腔排种滚筒的性能试验研究

针对现有气吸滚筒式排种器部件多、装配难、密封性差、无正压投种气室,以及难于实现正压投种清堵功能、直接造成排种器漏播率高的的技术问题,提出了利用3D快速成型技术打印剖分式负压吸种滚筒的新思路,并创新设计了双腔排种滚筒。以番茄种子为试验对象,以滚筒转速、滚筒负压和投种腔气室正压为试验因素,进行正交回归试验,并利用Design-Expert软件对试验数据进行方差分析和回归拟合,分析了影响排种性能指标的滚筒负压、滚筒转速和投种腔气室正压的显著性,确定了影响排种性能指标较优的结构参数、工作参数,即当投种腔气室正压为2.2k Pa、滚筒负压为2.4k Pa、滚筒转速为16r/min时,性能指标的最优值及为单粒率93.2%,重播率4.3%,漏播率2.5%,均满足精量排种的技术要求。     

稻麦变量施肥机控制系统设计与试验

针对稻麦变量施肥智能化程度低、通信系统可靠性和兼容性差等问题,研究设计了一种稻麦变量施肥机控制系统。该系统以CAN总线通讯作为现场总线,实现各控制节点之间的实时通信;通过GPS导航和处方图得到当前位置需肥量,根据变量施肥数学模型,通过步进电机节点实时调节外槽轮排肥器开度,实现施肥变量调节。试验结果表明:该系统机械结构设计合理,动作响应迅速,定位精准,各行排肥器之间排肥量变异系数最大为1. 78%,变量施肥精度达97%以上,作业效果良好。其控制程序稳定可靠,各控制节点之间通信及时、准确,整机设计合理,系统工作稳定,智能化程度高,各项技术指标满足农艺要求。     

虾料制粒机的压辊数量对颗粒品质的影响

压辊数量对虾料制粒机的颗粒品质有很大影响。文章分别对两压辊、三压辊结构进行分析,研究表明,两压辊制粒机较三压辊制粒机,更适宜用于虾料制粒。