Effects of nozzle type and spray angle on spray deposition in ivy pot plants

BACKGROUND: Fewer plant protection products are now authorised for use in ornamental growings. Frequent spraying with the same product or a suboptimal technique can lead to resistance in pests and diseases. Better application techniques could improve the sustainable use of the plant protection products still available. Spray boom systems—instead of the still predominantly used spray guns—might improve crop protection management in greenhouses considerably. The effect of nozzle type, spray pressure and spray angle on spray deposition and coverage in ivy pot plants was studied, with a focus on crop penetration and spraying the bottom side of the leaves in this dense crop. RESULTS: The experiments showed a significant and important effect of collector position on deposition and coverage in the plant. Although spray deposition and coverage on the bottom side of the leaves are generally low, they could be improved 3.0–4.9‐fold using the appropriate application technique. CONCLUSIONS: When using a spray boom in a dense crop, the nozzle choice, spray pressure and spray angle should be well considered. The hollow‐cone, the air‐inclusion flat‐fan and the standard flat‐fan nozzle with an inclined spray angle performed best because of the effect of swirling droplets, droplets with a high momentum and droplet direction respectively. Copyright © 2010 Society of Chemical Industry     

新疆地区主要灭蝗措施的分析及新机具的研制

本文分析了新疆地区近儿年来的蝗灾发生状况．以及所采取的各种有效的防治措施，提出了地面人工化学防治在灭蝗中所发挥的重要作用，并介绍了该地区最新研制的用于草原灭蝗的大型自走式超低量喷雾机具及其工作原理。     

6HW-12B型高射程喷雾机液压控制系统设计与计算

6HW-12B型高射程喷雾机是继6HW30型和6HW-12A型两种型号喷雾机研制成功后又一极具创新意义的新型森林病虫害防治设备。该机的主要特点是将6HW-12A型的“电控气动式“升级为“电控液压式”。介绍了该机型液压控制系统的设计与计算。     

Spray deposition in “tendone” vineyards when using a pneumatic electrostatic sprayer

The objective of this study was to evaluate the effect of electrostatic charge on foliar spray deposition in an Apulian “tendone” vineyard using an innovative pneumatic electrostatic sprayer. The sprayer was fitted with nozzles that linked the pneumatic atomization of the liquid, obtained using compressed air, to the electrostatic induction charge, thereby producing a stream of charged fine droplets. Furthermore, the sprayer was designed for low volume treatments, and the experimentation was carried out during a phenological stage with high leaf density to evaluate the performance of the machine under particularly challenging operative conditions.The sprayer was studied at three forward speeds (4, 5, and 6 km h⁻¹), and gave poor deposition inside the canopy, whether or not the electrostatic system was activated. Forward speed did not significantly affect the mean foliar spray deposition, whereas activation of the electrostatic system significantly increased the deposit only on the layer of foliage nearest to the sprayer (lower layer), but had no effect on deposition on the layer of foliage inside the canopy (upper layer). The ratio between the deposits on the two layers (lower:upper) was 6.5:1 when the electrostatic system was switched off, and 9.0:1 when it was switched on.However, this behaviour may allow targeted treatments on grapes, such as with Plant Protection Products (PPP) or bio growth stimulants. Furthermore, the small droplets produced by the machine are suitable for table grape protection because the droplets do not mark the grapes, which would reduce the quality of the product and its commercial value.     

轮距可调式喷雾机底盘驱动桥静强度分析及试验研究

为保证高地隙喷雾机底盘的可靠性,针对开发的高地隙喷雾机底盘及其轮距可调特性,建立了底盘驱动桥的三维模型,基于ANSYS软件对其静态结构强度进行了有限元分析研究,并对分析结果进行了试验验证。静强度分析结果与试验测量结果基本吻合。同时,结果表明,横管截面尺寸和壁厚对驱动桥的静强度有显著影响,采用截面尺寸为180 mm×130 mm、横管壁厚为15 mm的驱动桥完全能满足高地隙喷雾机底盘结构的强度要求,其产生的最大总变形对底盘性能的影响也可忽略。 采用该驱动桥时,底盘单侧轮距调出量从0 mm增加到400 mm,驱动桥产生的最大等效应力从159.7 MPa增大至285.17 MPa,驱动桥产生的最大总变形从1.04 mm增大至2.52 mm。该结果为保证轮距调节范围内高地隙底盘驱动桥强度的可靠性和满足变形范围要求提供了理论依据和数据支撑。     

杭州的四季茶会——Ⅱ.夏天的端午茶会

本文主要从缘起两个社团的"诞生日"、历次端午茶会的回顾和端午茶会的特色等三部分简要介绍了杭州四季茶会中之"夏天的端午茶会"。     

Sensor‐based assessment of herbicide effects

Non‐destructive assessment of herbicide effects may be able to support integrated weed management. To test whether effects of herbicides on canopy variables could be detected by sensors, two crops were used as models and treated with herbicides at BBCH 20 using a logarithmic sprayer. Twelve days after spraying at BBCH 25 and 42 days after sowing, nine sensor systems scanned a spring barley and an oilseed rape field experiment sown at different densities and sprayed with increasing field rates of glyphosate and tribenuron‐methyl. The objective was to compare ED₅₀s for crops and weeds derived by the different sensors in relation to crop density and herbicides. Although sensors were not directly developed to detect herbicide symptoms, they all detected changes in canopy colours or height and crop density. Generally ED₅₀s showed the same pattern in response to crop density within herbicide, but there were marked differences between barley and oilseed rape. We suggest that the results of comparing the various sensor outputs could become a stepping stone to future standardisation for the benefit of the research and development of sensors that will detect herbicide effect on crops and weeds, particularly at the most vulnerable stages of development of the canopy.     

喷雾技术对除草剂药效的影响

通过对喷雾器压力、喷嘴型号和药剂浓度的调节,对不同喷雾压力、不同喷嘴型号和不同药剂浓度下的除草效果进行调查分析,探讨影响喷雾质量的因素。结果表明：低压力范围内（30psi以下）,喷嘴型号越小,压力越高,雾化情况越好,防治效果好。     

风送喷雾机风量的选择与计算

风量是风送喷雾机的重要参数之一。本文介绍了以“置换原则”为基础的风量计算方法,并且提出了风送喷雾机风量的计算不仅要遵循“置换原则”,还应满足“末速度原则”的新概念。文中还结合大量的试验数据为这一概念提供了佐证。     

“Π”型循环喷雾机防飘性能试验

为适应篱架型作物病虫害防治要求,研制了能够将未沉积在靶标上的农药雾滴截留回收再利用的循环喷雾机,并与传统果园风送喷雾机进行了防飘性能对比试验。结果表明:在作业行下风向,"Π"型循环喷雾机空中飘失的药液比传统果园风送喷雾机减少了97.9%;在飘失距离内的地面飘失量比常规果园风送喷雾机减少了99.3%。