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51.
赵欣欣 《林业机械与木工设备》2011,39(8)
介绍了动力机械设备故障诊断技术,分析了制约其发展的主要因素,阐述了动力机械设备故障诊断技术的发展趋势。Abstract: The mechanical equipment diagnosis technology is introduced,the main factors restricting the development of mechanical equipment fault diagnosis technology are analyzed and the development trend of mechanical equipment fault diagnosis technology is stated 相似文献
52.
陈一收 《福建农业大学学报(哲学社会科学版)》2011,(1):30-33
构建和谐农村权力格局是有效农村治理的关键环节。作为一种理论架构,善治理论打破了"国家-社会"两分法的传统思维,追求工具理性与价值理性的有机耦合。以"善治"为分析框架和目标追求,从价值性、目的性、战略性三个维度厘清社会主义新农村建设中和谐农村权力格局的内涵,可以为实现国家与农村社会之间的良性互动提供理念支撑和价值取向。 相似文献
53.
The weight and composition of soybean seeds (Glycine Max L. Merrill) depend on changes in carbon and nitrogen assimilate supply during grain filling. Soybean pods and seeds are green, evidencing their capacity to capture light. However, the current physiological knowledge does not consider any effect of incident solar radiation reaching the pods on seed weight and composition. The objective of this work was to investigate the response of seed weight and composition to changes in assimilate supply from leaves, to the incident solar radiation reaching the pods and to the combination of both, changes in assimilate supply from the leaves and incident solar radiation on pods of soybean plants. Field experiments were performed during two growing seasons at Balcarce, Argentina. Treatments modified the amount of assimilates supplied by the leaves (plant shading, defoliation), the solar radiation reaching the pods (pod shading) or both (defoliation and pod shading) during seed filling. Plant shading and defoliation reduced seed weight, oil concentration and oil and protein content and increased the concentration of saturated and poli-unsaturated fatty acids while reduced oleic acid percentage. Pod shading increased the concentration of stearic acid and reduced the concentration of linolenic acid. When pods were shaded on defoliated plants, seed weight and oil and protein content decreased while fatty acid composition was similar to values obtained under defoliation treatment. Based on these results, a conceptual model that considers photoheterotrophic nature of reproductive structures of soybean is proposed. Seed weight, oil and protein content and oil fatty acid composition depended on assimilate availability for the seeds. The response of oil and protein content to assimilate supply depended on whether leaves were present or not. The effect of solar radiation incident on pods depended on the amount of assimilates available for the seeds: (i) when carbon allocated was low (defoliation treatments), pods contributed to seed carbon economy but solar radiation incident on them did not affect fatty acid composition; (ii) when carbon allocated to the seeds was high (intact plants), contribution of pods to seed carbon economy was not significant, but the amount of solar radiation incident on pods produced significant changes in fatty acid composition. 相似文献
54.
旋耕埋草机在作业过程中受到的阻力较大,尤其是在土壤粘重的地区作业,其功耗问题是制约该机发展的重要因素。针对高茬秸秆还田旋耕埋草机实际功耗大小不清楚、刀辊作业时运动参数与功耗的关系不明确等问题,根据功耗检测的基本原理,采用Delphi可视化编程软件,设计了一种新的旋耕埋草机功耗检测系统。该系统由4个模块组成,包括设计采集模块、传感器模块、数据分析模块和Delphi可视化显示模块。将该系统安装在旋耕埋草机上,对其性能进行了检测,并得到了转速、力矩和功耗等检测结果。该检测结果通过数据处理可以在Delphi开发的界面上进行可视化显示,为旋耕埋草机动力分配和节能降耗的研究提供了可借鉴的数据参考。 相似文献
55.
轨道交通的不断发展需要更多的电能,但当今能源日趋紧张,对节能降损必须予以足够的重视.所以轨道交通企业须在供电用电管理中加强线损的分析和预测,从供电设计、规划、管理等方面实施降低线损管理,使企业节能降耗并有效提高经济效益. 相似文献
56.
本文对太阳能的起源、传播、与物质的相互作用以及储存和利用等各个方面所涉及的物理学定律,特别是对太阳能热利用所涉及的热力学定律进行了概括和归纳。根据热力学定律指出太阳能热利用的真正适用范围。 相似文献
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As a large burning coal country, resolving the SO2 letting problem is the most important thing in the environment protection work. Electric power industry reveals the supply's load rate declining and the discrepancy between apex and vale augments year after year. It makes the load adjustment become an imminency task in the electric power industry. The article popularizes the light power saving technology in the inhabitant living lighting power through reinforcing the DSM technology. It studies the influence on energy and environment after using the technology. It studies avoidable electricity quantity, avoidable electricity power, avoidable apex load, avoidable coal consuming and avoidable SO2 lettling. At last, it makes a concrete analysis with a city's example. 相似文献
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