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《Communications in Soil Science and Plant Analysis》2012,43(11):1085-1091
Abstract Radlands Crimson strawberries were grown in a glasshouse with 7 rates of applied boron. Wood shavings mulches with different boron concentrations were also applied as separate treatments. Boron toxicity symptoms were produced in leaves by boron rates of 0.32 kg ha‐1 and greater on a soil containing 1.6 ug B g‐1 of hot water extractable boron. Concentrations greater than 123 μg B g‐1 in old leaves were associated with boron toxicity symptoms. In the B rate experiment, soil boron concentrations greater than 1.9 μg B g‐1 soil were associated with leaf toxicity symptoms which increased in severity with increasing soil boron concentrations up to 4.1 μg B g‐1 soil. Wood shavings mulch containing 17 μg B g‐1 caused boron toxicity symptoms in older leaves whereas mulches containing less than 6 μg B g‐1 did not produce toxicity symptoms. 相似文献
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本文介绍了一种适用于哈密瓜机械削皮机的仿形机构,并就其结构形式和主要结构尺寸进行了初步的设计。该仿形机构的特点是结构简单、仿形灵活,且仿形力可进行准确的变换。 相似文献
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利用日本三菱PLC定位控制单元的特点，研制了特形面数控刨床系统，相比传统的单片机控制系统，既简化了机床结构和控制系统，又简化了用户的编程工程，使系统的稳定性和灵活性得到了提高。 相似文献
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Rosilani Trianoski Setsuo Iwakiri Lucas Machado Thiago Souza da Rosa 《Journal of Sustainable Forestry》2017,36(8):833-846
The wood panel industry uses a large volume of wood and it is essential to research the use of new tree species for these types of products. As such, the aim of this study was to evaluate the feasibility of Cordia trichotoma (Vell.) wood, both on its own and as a mixture with Pinus spp., as well as to understand the effect on particleboard quality when adding the species’ bark and shavings. The experimental design included nine treatments that assessed various mixture proportations of C. trichotoma and Pinus; for example, 10% bark, and 10% shavings of C. trichotoma with Pinus spp. and C. trichotoma particles, as well as mixtures of these two species in proportions of 25/75%, 50%/50%, and 75/25%. The results indicate that the Cordia trichotoma specie is technically feasible when manufacturing particleboards in pure form. The incorporation of bark (at 10% of the mixture) is also technically feasible. It is also feasible to use the shavings of C. trichotoma. In general, all treatments produced outputs that showed dimensional stability and mechanical strength statistically equal or higher than control treatments (Pinus spp.); thus, these products may be used for non-structural applications in dry and/or moist conditions. 相似文献
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在木工机床运转情况及测量环境的满足国家标准的条件下，对ＣＴ５００型木工平面刨床进行噪声和振动测量。比较在不同情况（整机，拆出刀片，封上刀槽，无皮带罩，去除皮带）下噪声的大小及结构振动噪声发生的主要来源，分析各部件对整机噪声的影响，从而提出改进设计的意见。 相似文献
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