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11.
【目的】为了明确猕猴桃细菌性溃疡病的研究动态和进展,为该病的研究和防治提供参考。【方法】对1988-2015年期间中国知网中国期刊全文数据库上的猕猴桃细菌性溃疡病文献进行了统计分析。【结果】结果表明:我国猕猴桃细菌性溃疡病逐年加重,各猕猴桃产区发生不均衡;从文献研究内容上看,对猕猴桃细菌性溃疡病的防治和药剂筛选试验等内容较多,对病害的基础性研究以及规律、预测预报等方面研究较少。【结论】本文在详细分析文献的基础上提出了猕猴桃细菌性溃疡病的防控建议。 相似文献
12.
在研究翅片管加热器传热性能及流阻性能的基础上,依据热力学理论,利用不可逆过程Yong分析,着重分析管速换热过程的能量特性,将换热过程的传热性能与流阻性能有机地结合提出便于工程实际应用的能量特性分析准则函数。依此探讨管束换热过程特征参数对综合能量利用性能的影响,指导翅片管加热器能量的高效利用,并与光管加热器进行了比较分析。 相似文献
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D. Dimoyiannis 《Land Degradation \u0026amp; Development》2012,23(5):450-455
Aggregate stability is a fundamental property influencing soil erodibility and hydraulic characteristics. Knowledge of soil components controlling aggregate stability is very important to soil structure conservation. The objective of this study, which was carried out in surface soils from central Greece, was to relate wet aggregate stability to selected soil properties, with emphasis on excessive free carbonate content. The wet‐sieving technique of air‐dried aggregates was used for structural stability evaluation, according to a test that calculates an instability index. The soils studied were developed on Tertiary marly parent material and ranged in calcium carbonate content from 5 to 641 g kg−1. From the texture analysis before and after removal of carbonates, it was concluded that carbonates mainly contributed to total silt and sand fractions, that is to the mechanical fractions which, as a rule, negatively affect aggregate stability. The results of the correlation analysis showed that aggregate stability was positively affected by aluminosilicate clay content, cation exchange capacity (CEC) and Al‐containing sesquioxides. Clay fraction from carbonates and total sand and silt negatively affected aggregate stability. CEC has been proved a very significant determinant of aggregate stability, which in a hyperbolic form relationship with instability index explained 78·9 per cent of aggregate stability variation. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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本文讨论了节能式炉气干燥室设计的一些技术问题,如提高自生风引力增强通风;多种传热方式并用,增强传热,降低热损失的途径等,以达到节能降耗、快速干燥的目的。 相似文献
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基于赛博空间的图书馆员隐性知识共享 总被引:1,自引:0,他引:1
图书馆员的隐性知识是图书馆持续发展的动力,然而由于隐性知识本身特质导致其难以共享,其自身作用的发挥有所抑制。通过比较图书馆员隐性知识与赛博空间在文化特征方面的协调一致性,描述赛博空间对图书馆员隐性知识共享的拓展,凸显赛博空间是馆员隐性知识共享的有效方法。 相似文献
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K. M. Vlassak F. Mercante R. Straliotto A. Franco M. Vuylsteke J. Vanderleyden 《Biology and Fertility of Soils》1997,24(3):274-282
Inoculation of beans (Phaseolus vulgaris L.) with strains of R. tropici IIB and R. etli resulted in the disappearance of the R. tropici IIB stains from the nodule population and their replacement by other (non R. tropici IIB) bean symbionts (Vlassak et al. 1996). Coinoculation studies in monoxenic conditions and in soil core microcosms with
plants harvested at two different growth stages indicated that the inoculated R. tropici IIB strains CIAT899 and F98.5 possess a good intrinsic competitiveness which declines, however, at a later plant growth stage
and in soil conditions. The poor saprophytic competence of R. tropici IIB strain CIAT899 was further demonstrated by its poor survival in soil core microcosms after bean harvest. Strains were
isolated from the field plots with a 3-year bean-planting history, characterized and evaluated for their competitiveness against
R. tropici IIB strain CIAT899. Isolates from field plots, which had been repeatedly inoculated with R. tropici IIB strain CIAT899, showed a higher nodule occupancy compared to R. tropici IIB strain CIAT899, and this higher competitiveness exhibited by the field isolates might be an additional reason for the
poor performance of R. tropici IIB strain CIAT899 in the field study. Plots with and without a history of bean production revealed after 3-year bean cultivation
an almost totally different population that also significantly differed in competitiveness.
Received: 12 February 1996 相似文献
19.
6-BA缓解黄瓜弱光胁迫的浓度研究 总被引:1,自引:0,他引:1
在温室条件下,研究喷施不同浓度6-苄氨基嘌呤(6-BA)对弱光条件下不同类型黄瓜气体交换参数和叶绿素荧光参数的影响。结果表明,华南型杂交组合‘07QP56’在10 μmol/L 6-BA处理条件下,欧洲迷你型杂交组合‘07QP51’在2,5 μmol/L 6-BA 处理时,可以较为明显地缓解由弱光导致的饱和光合速率(Asat)、气孔导度(Gs)和蒸腾速率(Tr)降低的现象。同时,10 μmol/L 6-BA处理对缓解弱光下‘07QP56’的PSⅡ潜在活性(Fv/Fo)、原初光能转化效率(Fv/Fm)的降低也有一定的效果。‘07QP51’较‘07QP56’耐弱光,并且对高浓度6-BA处理也更为敏感。 相似文献
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