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91.
农业航空喷雾雾滴漂移及其数学分析 总被引:1,自引:0,他引:1
通过田间试验研究,探索了装配GP—81喷头的运五型飞机喷洒2,4—D丁酯乳油稀释液的雾滴漂移状况,建立了有关数学模型。研究表明,较低蒸发度的水雾滴漂移距离为340m,较高挥发度的2,4—D丁酯漂移距离达700m;雾滴密度和沉降量随下风距离增加而减小较快,雾滴直径减小较慢;气象因子和喷液配方对雾滴漂移有重要影响;三次多项式方程Y=b_0 b_1X b_2X~2 b_3X~3能很好地描述雾滴漂移与下风距离的关系,模型中的参数具有明确的实际意义,提出了喷洒2,4—D丁酯时的有效隔离带宽度。 相似文献
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Biological Control of Sclerotinia Diseases of Rapeseed by Aerial Applications of the Mycoparasite Coniothyrium minitans 总被引:1,自引:0,他引:1
G. Q. Li H. C. Huang H. J. Miao R. S. Erickson D. H. Jiang Y. N. Xiao 《European journal of plant pathology / European Foundation for Plant Pathology》2006,114(4):345-355
Indoor and field experiments were conducted to evaluate the efficacy of applying the mycoparasite Coniothyrium minitans to the aerial parts of rapeseed plants at the flowering stage to control sclerotinia diseases caused by Sclerotinia sclerotiorum. Under controlled conditions, a petal inoculation technique was used to determine the effect of conidial suspensions of C. minitans on suppression of sclerotinia leaf blight. Results showed that C. minitans was effective in inhibiting infection initiated by ascospores of S. sclerotiorum on flower petals by restricting mycelial growth of the pathogen. Suppression of lesion development was related to the conidial
concentration of C. minitans, with larger lesions at low concentration (5×103conidia ml−1), but smaller lesions at high concentration (5×104 conidia ml−1 or higher). When C. minitans-treated rapeseed leaves were inoculated with mycelia of S. sclerotiorum, C. minitans failed to prevent infection of leaves, but caused a significant reduction in number of sclerotia produced on the diseased
leaves. No significant difference in efficacy was detected between the two isolates of C. minitans, LRC 2137 and Chy-1, on the two rapeseed cultivars, Westar (spring type) and Zhongyou 821 (winter type). Results of field
trials showed a significant reduction of stem rot of rapeseed in four (1997, 1999, 2003 and 2004) out of five years by aerial
application of C. minitans, compared with controls. No significant difference in suppressive efficacy was observed between the treatments of C. minitans (106 conidia ml−1), C. minitans (106 conidia ml−1) + benomyl (50 μg ml−1) and benomyl (100 μg ml−1) in 2003, and between the treatments of C. minitans (106 conidia ml−1), C. minitans (106 conidia ml−1) + vinclozolin (100 μg ml−1) and vinclozolin (500 μg ml−1) in 2004. Sclerotia of S. sclerotiorum collected from diseased plants in plots treated with C. minitans in 1999, 2000 and 2003, or with C. minitans + benomyl in 2003 were infected by C. minitans at frequencies ranging from 21.3 to 54.5%. This study concludes that aerial spraying of C. minitans is an effective method for controlling sclerotinia diseases of rapeseed. 相似文献
94.
木材工业中干燥耗能与能源紧的矛盾日益突出,国外木材加企业在热能源自给方面技术已趋成熟,实施效果良好,为了增强国内企业节约能源的意识,本文详细测算分析了木材加工企业废料数量关系,提出了变废料为燃料、实现企业热能源自给的设想和依据。 相似文献
95.
旱区农业要大力推广喷灌与滴灌机械化 总被引:1,自引:0,他引:1
经过对喷灌与滴灌技术原理的探讨,提出旱区农业要发展推广喷灌和滴灌技术,并就喷灌与滴灌技术应用中的选型、配置、安装等方面的问题作分析。 相似文献
96.
《The Journal of Applied Poultry Research》2009,18(1):74-78
It is unclear how effective different types of broiler carcass wash steps are in lowering the presence or numbers of pathogenic bacteria. We tested for individual and combined effectiveness of 5 separate on-line wash steps applied between bleed-out and chilling in a commercial broiler processing plant. Carcasses were sampled directly before and after each wash step: pre-scald brush washer, post-feather pick (New York dressed) spray washer, inside/outside spray washer, postevisceration brush washer, and final prechill spray washer. Carcasses were examined for numbers of Campylobacter and Escherichia coli and presence of Salmonella using standard cultural methods. Overall, numbers of Campylobacter were lowered from log 2.58 to 1.15 cfu/mL of carcass rinse, but no single wash step caused a significant decrease. Overall, Salmonella prevalence was decreased from 80 to 24%; however, no wash step caused a significant decrease by itself. The 5 wash steps in series lowered E. coli numbers from log 4.60 to 2.69 cfu/mL; the New York-dressed spray wash and the postevisceration brush washer each had a significant effect on E. coli. When examined separately, the benefit of broiler carcass wash steps may not be evident. However, when combined with overall processing, wash steps can be effective to lessen bacterial contamination on carcasses and be useful for pathogen control. Additional studies are necessary to maximize the effectiveness of carcass washers. 相似文献
97.
王德丰 《东北林业大学学报》1990,18(6):62-68
PT-881型康明斯PT喷油器试验台是一种可移式试验装置。该试验台可与PT-821型PT泵试验台和任何型号的喷油泵试验台组合配套,对PT喷油器进行试验。喷油泵试验台仅用来驱动康明斯PT喷油器、变速和记录喷油次数。可移式试验装置可装在喷油泵试验台上并提供专用的驱动联轴节,以保持驱动PT喷油器的凸轮轴与喷油泵试验台驱动轴同轴。PT-881型康明斯PT喷油器试验台由凸轮箱、凸轮—挺杆机构、气动液压夹紧机构、气路系统和燃油系统组成。 相似文献
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