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71.
针对某车型样车在怠速开空调工况下方向盘存在异常抖动现象,首先通过试验的方法对该问题进行识别,然后通过进一步分析确定了问题原因为冷却风扇运转时引起方向盘共振、冷却风扇本体振动大以及传递路径隔振不足.为了消除方向盘异常抖动,提出了重新匹配风扇转速、控制风扇动不平衡量和优化散热器安装点隔振性能三项优化措施,并对样车进行试验和... 相似文献
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利用小型轴流风机通风降低仓库粮堆温度,通过对小功率轴流风机通风效果分析,观察粮食温度和风机能耗情况,分析其节能通风的效果。 相似文献
74.
利用功率5.5kW的离心风机和1.1kW的轴流风机,采用不同通风方法,抓住有利通风时机,分别对新收获江苏红小麦和山东白小麦通风。结果表明:山东白小麦使用4台1.1kW的轴流风机,抓住广州早春的低温高湿有利时机且平均粮温和气温差值在3℃时进行多次较长时间的通风,不仅保持了小麦品质良好,且通风效果理想,损耗正常,经济效益明显。 相似文献
75.
根据目前市场上对供料装置的特殊需求,设计出了一种新型的供料装置。新设计开发的供料器采用风机分流的气力侧面进给,吹动供料器叶片,使物料顺利落下。该供料器增强了密封性能,清洁方便,满足使用性能。其特点是:减少了一套驱动叶片旋转的传动装置,利用较为简单的结构形式,实现供料器的供料;并且体积小、重量轻、结构紧凑、制造容易、装调方便。 相似文献
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M. Mageed 《Equine Veterinary Education》2022,34(2):77-83
Computed tomography (CT) is an important cross-sectional diagnostic modality for lameness localised to the equine distal limb. The necessity of general anaesthesia to perform CT scans has limited its use in the equine orthopaedic field. Therefore, many attempts have been made to perform CT of the distal limb in standing horses. This retrospective report aims to describe the technical set-up and the feasibility of using a multi-slice helical CT unit recently introduced into the equine market. The medical records of the patients undergoing a standing CT in the period between March 2019 and January 2020 were reviewed. The imaged anatomical region and the image quality were assessed. Thirty-two horses met the inclusion criteria, and the following anatomical areas have been imaged: front foot/pastern (n = 14), metacarpophalangeal joint (n = 11), front proximal suspensory ligament (n = 2), carpus (n = 2), metatarsophalangeal joint (n = 2) and tarsus (n = 1). In 97% of the cases, excellent imaging quality was obtained. Motion artefact is the main cause of poor image quality. The feet and the metacarpophalangeal region can be easily imaged. Imaging the proximal anatomical regions of the limb is more challenging but achievable. 相似文献
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Arne Cierjacks Birgit Kleinschmit Maren Babinsky Fritz Kleinschroth Arvid Markert Markus Menzel Ulrike Ziechmann Theresa Schiller Markus Graf Friederike Lang 《植物养料与土壤学杂志》2010,173(5):644-653
Riparian forests are assumed to play a crucial role in the global carbon cycle. However, little data are available on C stocks of floodplains in comparison to other terrestrial ecosystems. In this study, we quantified the C stocks of aboveground biomass and soils of riparian vegetation types at 76 sampling sites in the Donau‐Auen National Park in Austria. Based on our results and a remotely sensed vegetation map, we estimated total C stocks. Carbon stocks in soils (up to 354 t ha–1 within 1 m below surface) were huge compared to other terrestrial ecosystems. As expected, soils of different vegetation types showed different texture with a higher percentage of sandy soils at the softwood sites, while loamy soils prevailed at hardwood sites. Total C stocks of vegetation types were significantly different, but reflect differences in woody plant biomass rather than in soil C stocks. Mature hardwood and cottonwood forests proved to have significantly higher total C stocks (474 and 403 t ha–1, respectively) than young reforestations (217 t ha–1) and meadows (212 t ha–1). The C pools of softwood forests (356 t ha–1) ranged between those of hardwood/cottonwood forests and of reforestations/meadows. Our study proves the relevance of floodplains as possible C sinks, which should be increasingly taken into account for river management. Furthermore, we conclude that plant‐species distribution does not indicate the conditions of sedimentation and soil C sequestration over the time span of interest for the development of soil C stocks. 相似文献
80.
白龙江中游泥石流冲积扇坡耕地开发潜力分析 总被引:2,自引:0,他引:2
泥石流冲积扇是山区难能可贵的相对平坦土地资源,对其进行开发利用对山区农业经济的发展具有重要意义。以白龙江中游泥石流冲积扇坡耕地为研究对象,通过野外考察,结合室内Quick Bird 10m分辨率卫星影像解译,选取冲积扇面积、灌溉水源、泥石流频率、防治措施、已开发比例5个评价因子,对白龙江中游泥石流冲积扇坡耕地的分布、开发利用现状、开发潜力进行了分析和评价。结果表明:一是白龙江中游172个泥石流冲积扇总面积约为30.0km2,占河谷平坦地面积的52.07%;二是泥石流冲积扇在白龙江干热河谷所占的面积相当大,开发潜力高的泥石流冲积扇坡耕地有90个,占总数的52.3%。由此可见,整个白龙江中游区泥石流冲积扇具有很好的开发潜力,其中以沙湾-固水子段的开发潜力最高。 相似文献