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131.
132.
水稻纸膜覆盖插秧机的设计 总被引:1,自引:0,他引:1
为加快纸膜覆盖水稻插秧技术的推广,提出设计水稻纸膜覆盖插秧机的基本思路,包括纸膜铺放机构、纸膜切断机构。该设计以期为以后生产样机和进一步优化设计水稻纸膜覆盖插秧机提供参考依据。 相似文献
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Objective To compare the tear‐film osmolarity of normal cats and cats with conjunctivitis. Animal studied The population consisted of shelter, research, and privately owned cats. Procedures Cats were classified as normal or having conjunctivitis. An ophthalmic examination including Schirmer tear test (STT), fluorescein staining, tear‐film break‐up time (TFBUT), intraocular pressure (IOP), and slit‐lamp biomicroscopy of the anterior segment was performed. The severity of conjunctivitis was graded and assigned a numerical score. The Tear LabTM Osmolarity System was utilized to determine the tear‐film osmolarity. Unpaired t‐tests were used to compare tear‐film osmolarity, TFBUT, IOP, and STT of the two groups. Results A total of 93 cats (186 eyes) were examined. There were 37 normal cats (74 eyes) and 39 conjunctivitis cats (78 eyes). The mean age was 2.34 years. There was no statistical difference (P = 0.2065) between the median tear‐film osmolarity of normal cats (328.5 ± 17.94 mOsms/L) and conjunctivitis cats (325.0 ± 24.84 mOsms/L). Cats with conjunctivitis had an accelerated TFBUT (P < 0.0001) and lower IOPs (P < 0.0001) as compared to normal cats. No statistical difference was found between STT values (P = 0.1304). Conclusions The median tear‐film osmolarity of normal cats was 328.5 mOsms/L. Despite the accelerated TFBUT, conjunctivitis did not cause a statistically significant change in tear‐film osmolarity. The Tear LabTM Osmolarity System was easily used and well tolerated by the cats in the study. 相似文献
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土壤水势测定方法的选择及准确性研究 总被引:1,自引:0,他引:1
通过对土壤水势常用的3种测定方法探讨,发现测定土壤水势的方法存在差别,压力膜的准确度为最高,其次是离心机,张力计的准确度较低.压力膜测定土壤水分特征曲线的形状与原状土壤的特征曲线大致相符,但要完整地测出某土壤的特征曲线需要长达半年之久.离心机测定土壤水分特征曲线较压力膜测定有偏离,离心机测定过程中土壤容重的不断变化、土... 相似文献
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BACKGROUND: The potato psyllid, Bactericera cockerelli, is a vector of Candidatus Liberibacter solanacearum, causing several diseases in solanaceous crops. Laboratory and field no‐choice and choice experiments were conducted to evaluate the repellency of kaolin particle film on adults of B. cockerelli on tomato plants that had been sprayed with kaolin particle film on the upper surface only, on the lower surface only and on both leaf surfaces. RESULTS: In no‐choice tests in the laboratory, the numbers of adults on leaves were not different between the kaolin particle film and the water control, regardless of which leaf surface(s) were treated, but numbers of eggs were lower on the leaves treated with kaolin particle film than on those treated with water. In choice tests on plants treated with water/plants treated with kaolin particle film at ratios of 1:1, 6:3 or 8:1, fewer adults and eggs were found on the leaves treated with kaolin particle film than on leaves treated with water. Under field conditions, in caged no‐choice or choice tests, fewer adults, eggs and nymphs were found on plants treated with kaolin particle film than on plants treated with water. In an uncaged test under field conditions, plants sprayed with kaolin particle film had fewer psyllids than those sprayed with water. CONCLUSION: Even though potato psyllid adults could land on plants treated with kaolin particle film when no choice was given, fewer eggs were laid. When given a choice, the psyllids avoided plants treated with kaolin particle film under laboratory and field conditions. Kaolin particle film treatment may be a useful alternative for management of potato psyllids under field conditions. Copyright © 2011 Society of Chemical Industry 相似文献
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冬小麦膜缝灌入渗模型试验研究 总被引:3,自引:0,他引:3
膜缝灌是一种新的灌水技术,其应用理论基础尚有待进一步研究。在大量的膜缝入渗和垂直一维入渗试验的基础上,分析了膜缝宽度和初始含水率对入渗参数的影响,根据试验分析,提出了包含膜缝宽度和初始含水率影响的入渗模型。这一研究对膜缝灌技术的应用研究将具有重要的价值。 相似文献
140.
涌泉灌溉用于大田作物主要问题是流量小,沟、畦横断面大,水流在田间很难向前推进。为此将其与垄膜沟种技术组合,缩小过水横断面,减小或杜绝侧渗,提高水流推进能力,这样可最大限度地减少灌水器(稳流器)数量,改善灌水质量,提高田间土壤水分的均匀度,进而为涌泉灌溉用于大田作物提供了可能性。采用涌泉灌溉配套垄膜沟种耕作方式,提高了降水的有效利用率,减少了灌水量与灌水次数、减少了棵间土壤水蒸发、农田耗水比一般大田灌溉节省28.3%。由于灌水量可控,比一般地面灌溉节约28%~47%。 相似文献